1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
//! [Flexible target specification.](https://github.com/rust-lang/rfcs/pull/131)
//!
//! Rust targets a wide variety of usecases, and in the interest of flexibility,
//! allows new target triples to be defined in configuration files. Most users
//! will not need to care about these, but this is invaluable when porting Rust
//! to a new platform, and allows for an unprecedented level of control over how
//! the compiler works.
//!
//! # Using custom targets
//!
//! A target triple, as passed via `rustc --target=TRIPLE`, will first be
//! compared against the list of built-in targets. This is to ease distributing
//! rustc (no need for configuration files) and also to hold these built-in
//! targets as immutable and sacred. If `TRIPLE` is not one of the built-in
//! targets, rustc will check if a file named `TRIPLE` exists. If it does, it
//! will be loaded as the target configuration. If the file does not exist,
//! rustc will search each directory in the environment variable
//! `RUST_TARGET_PATH` for a file named `TRIPLE.json`. The first one found will
//! be loaded. If no file is found in any of those directories, a fatal error
//! will be given.
//!
//! Projects defining their own targets should use
//! `--target=path/to/my-awesome-platform.json` instead of adding to
//! `RUST_TARGET_PATH`.
//!
//! # Defining a new target
//!
//! Targets are defined using [JSON](https://json.org/). The `Target` struct in
//! this module defines the format the JSON file should take, though each
//! underscore in the field names should be replaced with a hyphen (`-`) in the
//! JSON file. Some fields are required in every target specification, such as
//! `llvm-target`, `target-endian`, `target-pointer-width`, `data-layout`,
//! `arch`, and `os`. In general, options passed to rustc with `-C` override
//! the target's settings, though `target-feature` and `link-args` will *add*
//! to the list specified by the target, rather than replace.

use crate::abi::call::Conv;
use crate::abi::{Endian, Integer, Size, TargetDataLayout, TargetDataLayoutErrors};
use crate::json::{Json, ToJson};
use crate::spec::abi::{lookup as lookup_abi, Abi};
use crate::spec::crt_objects::{CrtObjects, LinkSelfContainedDefault};
use rustc_data_structures::stable_hasher::{HashStable, StableHasher};
use rustc_fs_util::try_canonicalize;
use rustc_serialize::{Decodable, Decoder, Encodable, Encoder};
use rustc_span::symbol::{kw, sym, Symbol};
use serde_json::Value;
use std::borrow::Cow;
use std::collections::BTreeMap;
use std::hash::{Hash, Hasher};
use std::ops::{Deref, DerefMut};
use std::path::{Path, PathBuf};
use std::str::FromStr;
use std::{fmt, io};

use rustc_macros::HashStable_Generic;

pub mod abi;
pub mod crt_objects;

mod aix_base;
mod android_base;
mod apple_base;
pub use apple_base::deployment_target as current_apple_deployment_target;
pub use apple_base::platform as current_apple_platform;
pub use apple_base::sdk_version as current_apple_sdk_version;
mod avr_gnu_base;
pub use avr_gnu_base::ef_avr_arch;
mod bpf_base;
mod dragonfly_base;
mod freebsd_base;
mod fuchsia_base;
mod haiku_base;
mod hermit_base;
mod hurd_base;
mod hurd_gnu_base;
mod illumos_base;
mod l4re_base;
mod linux_base;
mod linux_gnu_base;
mod linux_musl_base;
mod linux_ohos_base;
mod linux_uclibc_base;
mod msvc_base;
mod netbsd_base;
mod nto_qnx_base;
mod openbsd_base;
mod redox_base;
mod solaris_base;
mod solid_base;
mod teeos_base;
mod thumb_base;
mod uefi_msvc_base;
mod unikraft_linux_musl_base;
mod vxworks_base;
mod wasm_base;
mod windows_gnu_base;
mod windows_gnullvm_base;
mod windows_msvc_base;
mod windows_uwp_gnu_base;
mod windows_uwp_msvc_base;

/// Linker is called through a C/C++ compiler.
#[derive(Clone, Copy, Debug, Eq, Ord, PartialEq, PartialOrd)]
pub enum Cc {
    Yes,
    No,
}

/// Linker is LLD.
#[derive(Clone, Copy, Debug, Eq, Ord, PartialEq, PartialOrd)]
pub enum Lld {
    Yes,
    No,
}

/// All linkers have some kinds of command line interfaces and rustc needs to know which commands
/// to use with each of them. So we cluster all such interfaces into a (somewhat arbitrary) number
/// of classes that we call "linker flavors".
///
/// Technically, it's not even necessary, we can nearly always infer the flavor from linker name
/// and target properties like `is_like_windows`/`is_like_osx`/etc. However, the PRs originally
/// introducing `-Clinker-flavor` (#40018 and friends) were aiming to reduce this kind of inference
/// and provide something certain and explicitly specified instead, and that design goal is still
/// relevant now.
///
/// The second goal is to keep the number of flavors to the minimum if possible.
/// LLD somewhat forces our hand here because that linker is self-sufficient only if its executable
/// (`argv[0]`) is named in specific way, otherwise it doesn't work and requires a
/// `-flavor LLD_FLAVOR` argument to choose which logic to use. Our shipped `rust-lld` in
/// particular is not named in such specific way, so it needs the flavor option, so we make our
/// linker flavors sufficiently fine-grained to satisfy LLD without inferring its flavor from other
/// target properties, in accordance with the first design goal.
///
/// The first component of the flavor is tightly coupled with the compilation target,
/// while the `Cc` and `Lld` flags can vary within the same target.
#[derive(Clone, Copy, Debug, Eq, Ord, PartialEq, PartialOrd)]
pub enum LinkerFlavor {
    /// Unix-like linker with GNU extensions (both naked and compiler-wrapped forms).
    /// Besides similar "default" Linux/BSD linkers this also includes Windows/GNU linker,
    /// which is somewhat different because it doesn't produce ELFs.
    Gnu(Cc, Lld),
    /// Unix-like linker for Apple targets (both naked and compiler-wrapped forms).
    /// Extracted from the "umbrella" `Unix` flavor due to its corresponding LLD flavor.
    Darwin(Cc, Lld),
    /// Unix-like linker for Wasm targets (both naked and compiler-wrapped forms).
    /// Extracted from the "umbrella" `Unix` flavor due to its corresponding LLD flavor.
    /// Non-LLD version does not exist, so the lld flag is currently hardcoded here.
    WasmLld(Cc),
    /// Basic Unix-like linker for "any other Unix" targets (Solaris/illumos, L4Re, MSP430, etc),
    /// possibly with non-GNU extensions (both naked and compiler-wrapped forms).
    /// LLD doesn't support any of these.
    Unix(Cc),
    /// MSVC-style linker for Windows and UEFI, LLD supports it.
    Msvc(Lld),
    /// Emscripten Compiler Frontend, a wrapper around `WasmLld(Cc::Yes)` that has a different
    /// interface and produces some additional JavaScript output.
    EmCc,
    // Below: other linker-like tools with unique interfaces for exotic targets.
    /// Linker tool for BPF.
    Bpf,
    /// Linker tool for Nvidia PTX.
    Ptx,
}

/// Linker flavors available externally through command line (`-Clinker-flavor`)
/// or json target specifications.
/// FIXME: This set has accumulated historically, bring it more in line with the internal
/// linker flavors (`LinkerFlavor`).
#[derive(Clone, Copy, Debug, Eq, Ord, PartialEq, PartialOrd)]
pub enum LinkerFlavorCli {
    // New (unstable) flavors, with direct counterparts in `LinkerFlavor`.
    Gnu(Cc, Lld),
    Darwin(Cc, Lld),
    WasmLld(Cc),
    Unix(Cc),
    // Note: `Msvc(Lld::No)` is also a stable value.
    Msvc(Lld),
    EmCc,
    Bpf,
    Ptx,

    // Below: the legacy stable values.
    Gcc,
    Ld,
    Lld(LldFlavor),
    Em,
    BpfLinker,
    PtxLinker,
}

impl LinkerFlavorCli {
    /// Returns whether this `-C linker-flavor` option is one of the unstable values.
    pub fn is_unstable(&self) -> bool {
        match self {
            LinkerFlavorCli::Gnu(..)
            | LinkerFlavorCli::Darwin(..)
            | LinkerFlavorCli::WasmLld(..)
            | LinkerFlavorCli::Unix(..)
            | LinkerFlavorCli::Msvc(Lld::Yes)
            | LinkerFlavorCli::EmCc
            | LinkerFlavorCli::Bpf
            | LinkerFlavorCli::Ptx
            | LinkerFlavorCli::BpfLinker
            | LinkerFlavorCli::PtxLinker => true,
            LinkerFlavorCli::Gcc
            | LinkerFlavorCli::Ld
            | LinkerFlavorCli::Lld(..)
            | LinkerFlavorCli::Msvc(Lld::No)
            | LinkerFlavorCli::Em => false,
        }
    }
}

#[derive(Clone, Copy, Debug, Eq, Ord, PartialEq, PartialOrd)]
pub enum LldFlavor {
    Wasm,
    Ld64,
    Ld,
    Link,
}

impl LldFlavor {
    pub fn as_str(&self) -> &'static str {
        match self {
            LldFlavor::Wasm => "wasm",
            LldFlavor::Ld64 => "darwin",
            LldFlavor::Ld => "gnu",
            LldFlavor::Link => "link",
        }
    }

    fn from_str(s: &str) -> Option<Self> {
        Some(match s {
            "darwin" => LldFlavor::Ld64,
            "gnu" => LldFlavor::Ld,
            "link" => LldFlavor::Link,
            "wasm" => LldFlavor::Wasm,
            _ => return None,
        })
    }
}

impl ToJson for LldFlavor {
    fn to_json(&self) -> Json {
        self.as_str().to_json()
    }
}

impl LinkerFlavor {
    /// At this point the target's reference linker flavor doesn't yet exist and we need to infer
    /// it. The inference always succeds and gives some result, and we don't report any flavor
    /// incompatibility errors for json target specs. The CLI flavor is used as the main source
    /// of truth, other flags are used in case of ambiguities.
    fn from_cli_json(cli: LinkerFlavorCli, lld_flavor: LldFlavor, is_gnu: bool) -> LinkerFlavor {
        match cli {
            LinkerFlavorCli::Gnu(cc, lld) => LinkerFlavor::Gnu(cc, lld),
            LinkerFlavorCli::Darwin(cc, lld) => LinkerFlavor::Darwin(cc, lld),
            LinkerFlavorCli::WasmLld(cc) => LinkerFlavor::WasmLld(cc),
            LinkerFlavorCli::Unix(cc) => LinkerFlavor::Unix(cc),
            LinkerFlavorCli::Msvc(lld) => LinkerFlavor::Msvc(lld),
            LinkerFlavorCli::EmCc => LinkerFlavor::EmCc,
            LinkerFlavorCli::Bpf => LinkerFlavor::Bpf,
            LinkerFlavorCli::Ptx => LinkerFlavor::Ptx,

            // Below: legacy stable values
            LinkerFlavorCli::Gcc => match lld_flavor {
                LldFlavor::Ld if is_gnu => LinkerFlavor::Gnu(Cc::Yes, Lld::No),
                LldFlavor::Ld64 => LinkerFlavor::Darwin(Cc::Yes, Lld::No),
                LldFlavor::Wasm => LinkerFlavor::WasmLld(Cc::Yes),
                LldFlavor::Ld | LldFlavor::Link => LinkerFlavor::Unix(Cc::Yes),
            },
            LinkerFlavorCli::Ld => match lld_flavor {
                LldFlavor::Ld if is_gnu => LinkerFlavor::Gnu(Cc::No, Lld::No),
                LldFlavor::Ld64 => LinkerFlavor::Darwin(Cc::No, Lld::No),
                LldFlavor::Ld | LldFlavor::Wasm | LldFlavor::Link => LinkerFlavor::Unix(Cc::No),
            },
            LinkerFlavorCli::Lld(LldFlavor::Ld) => LinkerFlavor::Gnu(Cc::No, Lld::Yes),
            LinkerFlavorCli::Lld(LldFlavor::Ld64) => LinkerFlavor::Darwin(Cc::No, Lld::Yes),
            LinkerFlavorCli::Lld(LldFlavor::Wasm) => LinkerFlavor::WasmLld(Cc::No),
            LinkerFlavorCli::Lld(LldFlavor::Link) => LinkerFlavor::Msvc(Lld::Yes),
            LinkerFlavorCli::Em => LinkerFlavor::EmCc,
            LinkerFlavorCli::BpfLinker => LinkerFlavor::Bpf,
            LinkerFlavorCli::PtxLinker => LinkerFlavor::Ptx,
        }
    }

    fn to_cli(self) -> LinkerFlavorCli {
        match self {
            LinkerFlavor::Gnu(Cc::Yes, _)
            | LinkerFlavor::Darwin(Cc::Yes, _)
            | LinkerFlavor::WasmLld(Cc::Yes)
            | LinkerFlavor::Unix(Cc::Yes) => LinkerFlavorCli::Gcc,
            LinkerFlavor::Gnu(_, Lld::Yes) => LinkerFlavorCli::Lld(LldFlavor::Ld),
            LinkerFlavor::Darwin(_, Lld::Yes) => LinkerFlavorCli::Lld(LldFlavor::Ld64),
            LinkerFlavor::WasmLld(..) => LinkerFlavorCli::Lld(LldFlavor::Wasm),
            LinkerFlavor::Gnu(..) | LinkerFlavor::Darwin(..) | LinkerFlavor::Unix(..) => {
                LinkerFlavorCli::Ld
            }
            LinkerFlavor::Msvc(Lld::Yes) => LinkerFlavorCli::Lld(LldFlavor::Link),
            LinkerFlavor::Msvc(..) => LinkerFlavorCli::Msvc(Lld::No),
            LinkerFlavor::EmCc => LinkerFlavorCli::Em,
            LinkerFlavor::Bpf => LinkerFlavorCli::BpfLinker,
            LinkerFlavor::Ptx => LinkerFlavorCli::PtxLinker,
        }
    }

    fn infer_cli_hints(cli: LinkerFlavorCli) -> (Option<Cc>, Option<Lld>) {
        match cli {
            LinkerFlavorCli::Gnu(cc, lld) | LinkerFlavorCli::Darwin(cc, lld) => {
                (Some(cc), Some(lld))
            }
            LinkerFlavorCli::WasmLld(cc) => (Some(cc), Some(Lld::Yes)),
            LinkerFlavorCli::Unix(cc) => (Some(cc), None),
            LinkerFlavorCli::Msvc(lld) => (Some(Cc::No), Some(lld)),
            LinkerFlavorCli::EmCc => (Some(Cc::Yes), Some(Lld::Yes)),
            LinkerFlavorCli::Bpf | LinkerFlavorCli::Ptx => (None, None),

            // Below: legacy stable values
            LinkerFlavorCli::Gcc => (Some(Cc::Yes), None),
            LinkerFlavorCli::Ld => (Some(Cc::No), Some(Lld::No)),
            LinkerFlavorCli::Lld(_) => (Some(Cc::No), Some(Lld::Yes)),
            LinkerFlavorCli::Em => (Some(Cc::Yes), Some(Lld::Yes)),
            LinkerFlavorCli::BpfLinker | LinkerFlavorCli::PtxLinker => (None, None),
        }
    }

    fn infer_linker_hints(linker_stem: &str) -> (Option<Cc>, Option<Lld>) {
        // Remove any version postfix.
        let stem = linker_stem
            .rsplit_once('-')
            .and_then(|(lhs, rhs)| rhs.chars().all(char::is_numeric).then_some(lhs))
            .unwrap_or(linker_stem);

        // GCC/Clang can have an optional target prefix.
        if stem == "emcc"
            || stem == "gcc"
            || stem.ends_with("-gcc")
            || stem == "g++"
            || stem.ends_with("-g++")
            || stem == "clang"
            || stem.ends_with("-clang")
            || stem == "clang++"
            || stem.ends_with("-clang++")
        {
            (Some(Cc::Yes), Some(Lld::No))
        } else if stem == "wasm-ld"
            || stem.ends_with("-wasm-ld")
            || stem == "ld.lld"
            || stem == "lld"
            || stem == "rust-lld"
            || stem == "lld-link"
        {
            (Some(Cc::No), Some(Lld::Yes))
        } else if stem == "ld" || stem.ends_with("-ld") || stem == "link" {
            (Some(Cc::No), Some(Lld::No))
        } else {
            (None, None)
        }
    }

    fn with_hints(self, (cc_hint, lld_hint): (Option<Cc>, Option<Lld>)) -> LinkerFlavor {
        match self {
            LinkerFlavor::Gnu(cc, lld) => {
                LinkerFlavor::Gnu(cc_hint.unwrap_or(cc), lld_hint.unwrap_or(lld))
            }
            LinkerFlavor::Darwin(cc, lld) => {
                LinkerFlavor::Darwin(cc_hint.unwrap_or(cc), lld_hint.unwrap_or(lld))
            }
            LinkerFlavor::WasmLld(cc) => LinkerFlavor::WasmLld(cc_hint.unwrap_or(cc)),
            LinkerFlavor::Unix(cc) => LinkerFlavor::Unix(cc_hint.unwrap_or(cc)),
            LinkerFlavor::Msvc(lld) => LinkerFlavor::Msvc(lld_hint.unwrap_or(lld)),
            LinkerFlavor::EmCc | LinkerFlavor::Bpf | LinkerFlavor::Ptx => self,
        }
    }

    pub fn with_cli_hints(self, cli: LinkerFlavorCli) -> LinkerFlavor {
        self.with_hints(LinkerFlavor::infer_cli_hints(cli))
    }

    pub fn with_linker_hints(self, linker_stem: &str) -> LinkerFlavor {
        self.with_hints(LinkerFlavor::infer_linker_hints(linker_stem))
    }

    pub fn check_compatibility(self, cli: LinkerFlavorCli) -> Option<String> {
        let compatible = |cli| {
            // The CLI flavor should be compatible with the target if:
            // 1. they are counterparts: they have the same principal flavor.
            match (self, cli) {
                (LinkerFlavor::Gnu(..), LinkerFlavorCli::Gnu(..))
                | (LinkerFlavor::Darwin(..), LinkerFlavorCli::Darwin(..))
                | (LinkerFlavor::WasmLld(..), LinkerFlavorCli::WasmLld(..))
                | (LinkerFlavor::Unix(..), LinkerFlavorCli::Unix(..))
                | (LinkerFlavor::Msvc(..), LinkerFlavorCli::Msvc(..))
                | (LinkerFlavor::EmCc, LinkerFlavorCli::EmCc)
                | (LinkerFlavor::Bpf, LinkerFlavorCli::Bpf)
                | (LinkerFlavor::Ptx, LinkerFlavorCli::Ptx) => return true,
                _ => {}
            }

            // 2. or, the flavor is legacy and survives this roundtrip.
            cli == self.with_cli_hints(cli).to_cli()
        };
        (!compatible(cli)).then(|| {
            LinkerFlavorCli::all()
                .iter()
                .filter(|cli| compatible(**cli))
                .map(|cli| cli.desc())
                .intersperse(", ")
                .collect()
        })
    }

    pub fn lld_flavor(self) -> LldFlavor {
        match self {
            LinkerFlavor::Gnu(..)
            | LinkerFlavor::Unix(..)
            | LinkerFlavor::EmCc
            | LinkerFlavor::Bpf
            | LinkerFlavor::Ptx => LldFlavor::Ld,
            LinkerFlavor::Darwin(..) => LldFlavor::Ld64,
            LinkerFlavor::WasmLld(..) => LldFlavor::Wasm,
            LinkerFlavor::Msvc(..) => LldFlavor::Link,
        }
    }

    pub fn is_gnu(self) -> bool {
        matches!(self, LinkerFlavor::Gnu(..))
    }

    /// Returns whether the flavor uses the `lld` linker.
    pub fn uses_lld(self) -> bool {
        // Exhaustive match in case new flavors are added in the future.
        match self {
            LinkerFlavor::Gnu(_, Lld::Yes)
            | LinkerFlavor::Darwin(_, Lld::Yes)
            | LinkerFlavor::WasmLld(..)
            | LinkerFlavor::EmCc
            | LinkerFlavor::Msvc(Lld::Yes) => true,
            LinkerFlavor::Gnu(..)
            | LinkerFlavor::Darwin(..)
            | LinkerFlavor::Msvc(_)
            | LinkerFlavor::Unix(_)
            | LinkerFlavor::Bpf
            | LinkerFlavor::Ptx => false,
        }
    }

    /// Returns whether the flavor calls the linker via a C/C++ compiler.
    pub fn uses_cc(self) -> bool {
        // Exhaustive match in case new flavors are added in the future.
        match self {
            LinkerFlavor::Gnu(Cc::Yes, _)
            | LinkerFlavor::Darwin(Cc::Yes, _)
            | LinkerFlavor::WasmLld(Cc::Yes)
            | LinkerFlavor::Unix(Cc::Yes)
            | LinkerFlavor::EmCc => true,
            LinkerFlavor::Gnu(..)
            | LinkerFlavor::Darwin(..)
            | LinkerFlavor::WasmLld(_)
            | LinkerFlavor::Msvc(_)
            | LinkerFlavor::Unix(_)
            | LinkerFlavor::Bpf
            | LinkerFlavor::Ptx => false,
        }
    }
}

macro_rules! linker_flavor_cli_impls {
    ($(($($flavor:tt)*) $string:literal)*) => (
        impl LinkerFlavorCli {
            const fn all() -> &'static [LinkerFlavorCli] {
                &[$($($flavor)*,)*]
            }

            pub const fn one_of() -> &'static str {
                concat!("one of: ", $($string, " ",)*)
            }

            pub fn from_str(s: &str) -> Option<LinkerFlavorCli> {
                Some(match s {
                    $($string => $($flavor)*,)*
                    _ => return None,
                })
            }

            pub fn desc(self) -> &'static str {
                match self {
                    $($($flavor)* => $string,)*
                }
            }
        }
    )
}

linker_flavor_cli_impls! {
    (LinkerFlavorCli::Gnu(Cc::No, Lld::No)) "gnu"
    (LinkerFlavorCli::Gnu(Cc::No, Lld::Yes)) "gnu-lld"
    (LinkerFlavorCli::Gnu(Cc::Yes, Lld::No)) "gnu-cc"
    (LinkerFlavorCli::Gnu(Cc::Yes, Lld::Yes)) "gnu-lld-cc"
    (LinkerFlavorCli::Darwin(Cc::No, Lld::No)) "darwin"
    (LinkerFlavorCli::Darwin(Cc::No, Lld::Yes)) "darwin-lld"
    (LinkerFlavorCli::Darwin(Cc::Yes, Lld::No)) "darwin-cc"
    (LinkerFlavorCli::Darwin(Cc::Yes, Lld::Yes)) "darwin-lld-cc"
    (LinkerFlavorCli::WasmLld(Cc::No)) "wasm-lld"
    (LinkerFlavorCli::WasmLld(Cc::Yes)) "wasm-lld-cc"
    (LinkerFlavorCli::Unix(Cc::No)) "unix"
    (LinkerFlavorCli::Unix(Cc::Yes)) "unix-cc"
    (LinkerFlavorCli::Msvc(Lld::Yes)) "msvc-lld"
    (LinkerFlavorCli::Msvc(Lld::No)) "msvc"
    (LinkerFlavorCli::EmCc) "em-cc"
    (LinkerFlavorCli::Bpf) "bpf"
    (LinkerFlavorCli::Ptx) "ptx"

    // Below: legacy stable values
    (LinkerFlavorCli::Gcc) "gcc"
    (LinkerFlavorCli::Ld) "ld"
    (LinkerFlavorCli::Lld(LldFlavor::Ld)) "ld.lld"
    (LinkerFlavorCli::Lld(LldFlavor::Ld64)) "ld64.lld"
    (LinkerFlavorCli::Lld(LldFlavor::Link)) "lld-link"
    (LinkerFlavorCli::Lld(LldFlavor::Wasm)) "wasm-ld"
    (LinkerFlavorCli::Em) "em"
    (LinkerFlavorCli::BpfLinker) "bpf-linker"
    (LinkerFlavorCli::PtxLinker) "ptx-linker"
}

impl ToJson for LinkerFlavorCli {
    fn to_json(&self) -> Json {
        self.desc().to_json()
    }
}

#[derive(Clone, Copy, Debug, PartialEq, Hash, Encodable, Decodable, HashStable_Generic)]
pub enum PanicStrategy {
    Unwind,
    Abort,
}

impl PanicStrategy {
    pub fn desc(&self) -> &str {
        match *self {
            PanicStrategy::Unwind => "unwind",
            PanicStrategy::Abort => "abort",
        }
    }

    pub const fn desc_symbol(&self) -> Symbol {
        match *self {
            PanicStrategy::Unwind => sym::unwind,
            PanicStrategy::Abort => sym::abort,
        }
    }

    pub const fn all() -> [Symbol; 2] {
        [Self::Abort.desc_symbol(), Self::Unwind.desc_symbol()]
    }
}

impl ToJson for PanicStrategy {
    fn to_json(&self) -> Json {
        match *self {
            PanicStrategy::Abort => "abort".to_json(),
            PanicStrategy::Unwind => "unwind".to_json(),
        }
    }
}

#[derive(Clone, Copy, Debug, PartialEq, Hash)]
pub enum RelroLevel {
    Full,
    Partial,
    Off,
    None,
}

impl RelroLevel {
    pub fn desc(&self) -> &str {
        match *self {
            RelroLevel::Full => "full",
            RelroLevel::Partial => "partial",
            RelroLevel::Off => "off",
            RelroLevel::None => "none",
        }
    }
}

impl FromStr for RelroLevel {
    type Err = ();

    fn from_str(s: &str) -> Result<RelroLevel, ()> {
        match s {
            "full" => Ok(RelroLevel::Full),
            "partial" => Ok(RelroLevel::Partial),
            "off" => Ok(RelroLevel::Off),
            "none" => Ok(RelroLevel::None),
            _ => Err(()),
        }
    }
}

impl ToJson for RelroLevel {
    fn to_json(&self) -> Json {
        match *self {
            RelroLevel::Full => "full".to_json(),
            RelroLevel::Partial => "partial".to_json(),
            RelroLevel::Off => "off".to_json(),
            RelroLevel::None => "None".to_json(),
        }
    }
}

#[derive(Clone, Copy, Debug, PartialEq, Hash)]
pub enum MergeFunctions {
    Disabled,
    Trampolines,
    Aliases,
}

impl MergeFunctions {
    pub fn desc(&self) -> &str {
        match *self {
            MergeFunctions::Disabled => "disabled",
            MergeFunctions::Trampolines => "trampolines",
            MergeFunctions::Aliases => "aliases",
        }
    }
}

impl FromStr for MergeFunctions {
    type Err = ();

    fn from_str(s: &str) -> Result<MergeFunctions, ()> {
        match s {
            "disabled" => Ok(MergeFunctions::Disabled),
            "trampolines" => Ok(MergeFunctions::Trampolines),
            "aliases" => Ok(MergeFunctions::Aliases),
            _ => Err(()),
        }
    }
}

impl ToJson for MergeFunctions {
    fn to_json(&self) -> Json {
        match *self {
            MergeFunctions::Disabled => "disabled".to_json(),
            MergeFunctions::Trampolines => "trampolines".to_json(),
            MergeFunctions::Aliases => "aliases".to_json(),
        }
    }
}

#[derive(Clone, Copy, PartialEq, Hash, Debug)]
pub enum RelocModel {
    Static,
    Pic,
    Pie,
    DynamicNoPic,
    Ropi,
    Rwpi,
    RopiRwpi,
}

impl RelocModel {
    pub fn desc(&self) -> &str {
        match *self {
            RelocModel::Static => "static",
            RelocModel::Pic => "pic",
            RelocModel::Pie => "pie",
            RelocModel::DynamicNoPic => "dynamic-no-pic",
            RelocModel::Ropi => "ropi",
            RelocModel::Rwpi => "rwpi",
            RelocModel::RopiRwpi => "ropi-rwpi",
        }
    }
    pub const fn desc_symbol(&self) -> Symbol {
        match *self {
            RelocModel::Static => kw::Static,
            RelocModel::Pic => sym::pic,
            RelocModel::Pie => sym::pie,
            RelocModel::DynamicNoPic => sym::dynamic_no_pic,
            RelocModel::Ropi => sym::ropi,
            RelocModel::Rwpi => sym::rwpi,
            RelocModel::RopiRwpi => sym::ropi_rwpi,
        }
    }

    pub const fn all() -> [Symbol; 7] {
        [
            RelocModel::Static.desc_symbol(),
            RelocModel::Pic.desc_symbol(),
            RelocModel::Pie.desc_symbol(),
            RelocModel::DynamicNoPic.desc_symbol(),
            RelocModel::Ropi.desc_symbol(),
            RelocModel::Rwpi.desc_symbol(),
            RelocModel::RopiRwpi.desc_symbol(),
        ]
    }
}

impl FromStr for RelocModel {
    type Err = ();

    fn from_str(s: &str) -> Result<RelocModel, ()> {
        Ok(match s {
            "static" => RelocModel::Static,
            "pic" => RelocModel::Pic,
            "pie" => RelocModel::Pie,
            "dynamic-no-pic" => RelocModel::DynamicNoPic,
            "ropi" => RelocModel::Ropi,
            "rwpi" => RelocModel::Rwpi,
            "ropi-rwpi" => RelocModel::RopiRwpi,
            _ => return Err(()),
        })
    }
}

impl ToJson for RelocModel {
    fn to_json(&self) -> Json {
        self.desc().to_json()
    }
}

#[derive(Clone, Copy, PartialEq, Hash, Debug)]
pub enum CodeModel {
    Tiny,
    Small,
    Kernel,
    Medium,
    Large,
}

impl FromStr for CodeModel {
    type Err = ();

    fn from_str(s: &str) -> Result<CodeModel, ()> {
        Ok(match s {
            "tiny" => CodeModel::Tiny,
            "small" => CodeModel::Small,
            "kernel" => CodeModel::Kernel,
            "medium" => CodeModel::Medium,
            "large" => CodeModel::Large,
            _ => return Err(()),
        })
    }
}

impl ToJson for CodeModel {
    fn to_json(&self) -> Json {
        match *self {
            CodeModel::Tiny => "tiny",
            CodeModel::Small => "small",
            CodeModel::Kernel => "kernel",
            CodeModel::Medium => "medium",
            CodeModel::Large => "large",
        }
        .to_json()
    }
}

#[derive(Clone, Copy, PartialEq, Hash, Debug)]
pub enum TlsModel {
    GeneralDynamic,
    LocalDynamic,
    InitialExec,
    LocalExec,
}

impl FromStr for TlsModel {
    type Err = ();

    fn from_str(s: &str) -> Result<TlsModel, ()> {
        Ok(match s {
            // Note the difference "general" vs "global" difference. The model name is "general",
            // but the user-facing option name is "global" for consistency with other compilers.
            "global-dynamic" => TlsModel::GeneralDynamic,
            "local-dynamic" => TlsModel::LocalDynamic,
            "initial-exec" => TlsModel::InitialExec,
            "local-exec" => TlsModel::LocalExec,
            _ => return Err(()),
        })
    }
}

impl ToJson for TlsModel {
    fn to_json(&self) -> Json {
        match *self {
            TlsModel::GeneralDynamic => "global-dynamic",
            TlsModel::LocalDynamic => "local-dynamic",
            TlsModel::InitialExec => "initial-exec",
            TlsModel::LocalExec => "local-exec",
        }
        .to_json()
    }
}

/// Everything is flattened to a single enum to make the json encoding/decoding less annoying.
#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Debug)]
pub enum LinkOutputKind {
    /// Dynamically linked non position-independent executable.
    DynamicNoPicExe,
    /// Dynamically linked position-independent executable.
    DynamicPicExe,
    /// Statically linked non position-independent executable.
    StaticNoPicExe,
    /// Statically linked position-independent executable.
    StaticPicExe,
    /// Regular dynamic library ("dynamically linked").
    DynamicDylib,
    /// Dynamic library with bundled libc ("statically linked").
    StaticDylib,
    /// WASI module with a lifetime past the _initialize entry point
    WasiReactorExe,
}

impl LinkOutputKind {
    fn as_str(&self) -> &'static str {
        match self {
            LinkOutputKind::DynamicNoPicExe => "dynamic-nopic-exe",
            LinkOutputKind::DynamicPicExe => "dynamic-pic-exe",
            LinkOutputKind::StaticNoPicExe => "static-nopic-exe",
            LinkOutputKind::StaticPicExe => "static-pic-exe",
            LinkOutputKind::DynamicDylib => "dynamic-dylib",
            LinkOutputKind::StaticDylib => "static-dylib",
            LinkOutputKind::WasiReactorExe => "wasi-reactor-exe",
        }
    }

    pub(super) fn from_str(s: &str) -> Option<LinkOutputKind> {
        Some(match s {
            "dynamic-nopic-exe" => LinkOutputKind::DynamicNoPicExe,
            "dynamic-pic-exe" => LinkOutputKind::DynamicPicExe,
            "static-nopic-exe" => LinkOutputKind::StaticNoPicExe,
            "static-pic-exe" => LinkOutputKind::StaticPicExe,
            "dynamic-dylib" => LinkOutputKind::DynamicDylib,
            "static-dylib" => LinkOutputKind::StaticDylib,
            "wasi-reactor-exe" => LinkOutputKind::WasiReactorExe,
            _ => return None,
        })
    }

    pub fn can_link_dylib(self) -> bool {
        match self {
            LinkOutputKind::StaticNoPicExe | LinkOutputKind::StaticPicExe => false,
            LinkOutputKind::DynamicNoPicExe
            | LinkOutputKind::DynamicPicExe
            | LinkOutputKind::DynamicDylib
            | LinkOutputKind::StaticDylib
            | LinkOutputKind::WasiReactorExe => true,
        }
    }
}

impl fmt::Display for LinkOutputKind {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.write_str(self.as_str())
    }
}

pub type LinkArgs = BTreeMap<LinkerFlavor, Vec<StaticCow<str>>>;
pub type LinkArgsCli = BTreeMap<LinkerFlavorCli, Vec<StaticCow<str>>>;

/// Which kind of debuginfo does the target use?
///
/// Useful in determining whether a target supports Split DWARF (a target with
/// `DebuginfoKind::Dwarf` and supporting `SplitDebuginfo::Unpacked` for example).
#[derive(Clone, Copy, Debug, Default, Eq, Hash, PartialEq)]
pub enum DebuginfoKind {
    /// DWARF debuginfo (such as that used on `x86_64_unknown_linux_gnu`).
    #[default]
    Dwarf,
    /// DWARF debuginfo in dSYM files (such as on Apple platforms).
    DwarfDsym,
    /// Program database files (such as on Windows).
    Pdb,
}

impl DebuginfoKind {
    fn as_str(&self) -> &'static str {
        match self {
            DebuginfoKind::Dwarf => "dwarf",
            DebuginfoKind::DwarfDsym => "dwarf-dsym",
            DebuginfoKind::Pdb => "pdb",
        }
    }
}

impl FromStr for DebuginfoKind {
    type Err = ();

    fn from_str(s: &str) -> Result<Self, ()> {
        Ok(match s {
            "dwarf" => DebuginfoKind::Dwarf,
            "dwarf-dsym" => DebuginfoKind::DwarfDsym,
            "pdb" => DebuginfoKind::Pdb,
            _ => return Err(()),
        })
    }
}

impl ToJson for DebuginfoKind {
    fn to_json(&self) -> Json {
        self.as_str().to_json()
    }
}

impl fmt::Display for DebuginfoKind {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.write_str(self.as_str())
    }
}

#[derive(Clone, Copy, Debug, Default, Eq, Hash, PartialEq)]
pub enum SplitDebuginfo {
    /// Split debug-information is disabled, meaning that on supported platforms
    /// you can find all debug information in the executable itself. This is
    /// only supported for ELF effectively.
    ///
    /// * Windows - not supported
    /// * macOS - don't run `dsymutil`
    /// * ELF - `.debug_*` sections
    #[default]
    Off,

    /// Split debug-information can be found in a "packed" location separate
    /// from the final artifact. This is supported on all platforms.
    ///
    /// * Windows - `*.pdb`
    /// * macOS - `*.dSYM` (run `dsymutil`)
    /// * ELF - `*.dwp` (run `thorin`)
    Packed,

    /// Split debug-information can be found in individual object files on the
    /// filesystem. The main executable may point to the object files.
    ///
    /// * Windows - not supported
    /// * macOS - supported, scattered object files
    /// * ELF - supported, scattered `*.dwo` or `*.o` files (see `SplitDwarfKind`)
    Unpacked,
}

impl SplitDebuginfo {
    fn as_str(&self) -> &'static str {
        match self {
            SplitDebuginfo::Off => "off",
            SplitDebuginfo::Packed => "packed",
            SplitDebuginfo::Unpacked => "unpacked",
        }
    }
}

impl FromStr for SplitDebuginfo {
    type Err = ();

    fn from_str(s: &str) -> Result<Self, ()> {
        Ok(match s {
            "off" => SplitDebuginfo::Off,
            "unpacked" => SplitDebuginfo::Unpacked,
            "packed" => SplitDebuginfo::Packed,
            _ => return Err(()),
        })
    }
}

impl ToJson for SplitDebuginfo {
    fn to_json(&self) -> Json {
        self.as_str().to_json()
    }
}

impl fmt::Display for SplitDebuginfo {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.write_str(self.as_str())
    }
}

#[derive(Clone, Debug, PartialEq, Eq)]
pub enum StackProbeType {
    /// Don't emit any stack probes.
    None,
    /// It is harmless to use this option even on targets that do not have backend support for
    /// stack probes as the failure mode is the same as if no stack-probe option was specified in
    /// the first place.
    Inline,
    /// Call `__rust_probestack` whenever stack needs to be probed.
    Call,
    /// Use inline option for LLVM versions later than specified in `min_llvm_version_for_inline`
    /// and call `__rust_probestack` otherwise.
    InlineOrCall { min_llvm_version_for_inline: (u32, u32, u32) },
}

impl StackProbeType {
    // LLVM X86 targets (ix86 and x86_64) can use inline-asm stack probes starting with LLVM 16.
    // Notable past issues were rust#83139 (fixed in 14) and rust#84667 (fixed in 16).
    const X86: Self = Self::InlineOrCall { min_llvm_version_for_inline: (16, 0, 0) };

    fn from_json(json: &Json) -> Result<Self, String> {
        let object = json.as_object().ok_or_else(|| "expected a JSON object")?;
        let kind = object
            .get("kind")
            .and_then(|o| o.as_str())
            .ok_or_else(|| "expected `kind` to be a string")?;
        match kind {
            "none" => Ok(StackProbeType::None),
            "inline" => Ok(StackProbeType::Inline),
            "call" => Ok(StackProbeType::Call),
            "inline-or-call" => {
                let min_version = object
                    .get("min-llvm-version-for-inline")
                    .and_then(|o| o.as_array())
                    .ok_or_else(|| "expected `min-llvm-version-for-inline` to be an array")?;
                let mut iter = min_version.into_iter().map(|v| {
                    let int = v.as_u64().ok_or_else(
                        || "expected `min-llvm-version-for-inline` values to be integers",
                    )?;
                    u32::try_from(int)
                        .map_err(|_| "`min-llvm-version-for-inline` values don't convert to u32")
                });
                let min_llvm_version_for_inline = (
                    iter.next().unwrap_or(Ok(11))?,
                    iter.next().unwrap_or(Ok(0))?,
                    iter.next().unwrap_or(Ok(0))?,
                );
                Ok(StackProbeType::InlineOrCall { min_llvm_version_for_inline })
            }
            _ => Err(String::from(
                "`kind` expected to be one of `none`, `inline`, `call` or `inline-or-call`",
            )),
        }
    }
}

impl ToJson for StackProbeType {
    fn to_json(&self) -> Json {
        Json::Object(match self {
            StackProbeType::None => {
                [(String::from("kind"), "none".to_json())].into_iter().collect()
            }
            StackProbeType::Inline => {
                [(String::from("kind"), "inline".to_json())].into_iter().collect()
            }
            StackProbeType::Call => {
                [(String::from("kind"), "call".to_json())].into_iter().collect()
            }
            StackProbeType::InlineOrCall { min_llvm_version_for_inline: (maj, min, patch) } => [
                (String::from("kind"), "inline-or-call".to_json()),
                (
                    String::from("min-llvm-version-for-inline"),
                    Json::Array(vec![maj.to_json(), min.to_json(), patch.to_json()]),
                ),
            ]
            .into_iter()
            .collect(),
        })
    }
}

bitflags::bitflags! {
    #[derive(Default, Encodable, Decodable)]
    pub struct SanitizerSet: u16 {
        const ADDRESS = 1 << 0;
        const LEAK    = 1 << 1;
        const MEMORY  = 1 << 2;
        const THREAD  = 1 << 3;
        const HWADDRESS = 1 << 4;
        const CFI     = 1 << 5;
        const MEMTAG  = 1 << 6;
        const SHADOWCALLSTACK = 1 << 7;
        const KCFI    = 1 << 8;
        const KERNELADDRESS = 1 << 9;
        const SAFESTACK = 1 << 10;
    }
}

impl SanitizerSet {
    /// Return sanitizer's name
    ///
    /// Returns none if the flags is a set of sanitizers numbering not exactly one.
    pub fn as_str(self) -> Option<&'static str> {
        Some(match self {
            SanitizerSet::ADDRESS => "address",
            SanitizerSet::CFI => "cfi",
            SanitizerSet::KCFI => "kcfi",
            SanitizerSet::KERNELADDRESS => "kernel-address",
            SanitizerSet::LEAK => "leak",
            SanitizerSet::MEMORY => "memory",
            SanitizerSet::MEMTAG => "memtag",
            SanitizerSet::SAFESTACK => "safestack",
            SanitizerSet::SHADOWCALLSTACK => "shadow-call-stack",
            SanitizerSet::THREAD => "thread",
            SanitizerSet::HWADDRESS => "hwaddress",
            _ => return None,
        })
    }
}

/// Formats a sanitizer set as a comma separated list of sanitizers' names.
impl fmt::Display for SanitizerSet {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        let mut first = true;
        for s in *self {
            let name = s.as_str().unwrap_or_else(|| panic!("unrecognized sanitizer {s:?}"));
            if !first {
                f.write_str(", ")?;
            }
            f.write_str(name)?;
            first = false;
        }
        Ok(())
    }
}

impl IntoIterator for SanitizerSet {
    type Item = SanitizerSet;
    type IntoIter = std::vec::IntoIter<SanitizerSet>;

    fn into_iter(self) -> Self::IntoIter {
        [
            SanitizerSet::ADDRESS,
            SanitizerSet::CFI,
            SanitizerSet::KCFI,
            SanitizerSet::LEAK,
            SanitizerSet::MEMORY,
            SanitizerSet::MEMTAG,
            SanitizerSet::SHADOWCALLSTACK,
            SanitizerSet::THREAD,
            SanitizerSet::HWADDRESS,
            SanitizerSet::KERNELADDRESS,
            SanitizerSet::SAFESTACK,
        ]
        .iter()
        .copied()
        .filter(|&s| self.contains(s))
        .collect::<Vec<_>>()
        .into_iter()
    }
}

impl<CTX> HashStable<CTX> for SanitizerSet {
    fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher) {
        self.bits().hash_stable(ctx, hasher);
    }
}

impl ToJson for SanitizerSet {
    fn to_json(&self) -> Json {
        self.into_iter()
            .map(|v| Some(v.as_str()?.to_json()))
            .collect::<Option<Vec<_>>>()
            .unwrap_or_default()
            .to_json()
    }
}

#[derive(Clone, Copy, PartialEq, Hash, Debug)]
pub enum FramePointer {
    /// Forces the machine code generator to always preserve the frame pointers.
    Always,
    /// Forces the machine code generator to preserve the frame pointers except for the leaf
    /// functions (i.e. those that don't call other functions).
    NonLeaf,
    /// Allows the machine code generator to omit the frame pointers.
    ///
    /// This option does not guarantee that the frame pointers will be omitted.
    MayOmit,
}

impl FromStr for FramePointer {
    type Err = ();
    fn from_str(s: &str) -> Result<Self, ()> {
        Ok(match s {
            "always" => Self::Always,
            "non-leaf" => Self::NonLeaf,
            "may-omit" => Self::MayOmit,
            _ => return Err(()),
        })
    }
}

impl ToJson for FramePointer {
    fn to_json(&self) -> Json {
        match *self {
            Self::Always => "always",
            Self::NonLeaf => "non-leaf",
            Self::MayOmit => "may-omit",
        }
        .to_json()
    }
}

/// Controls use of stack canaries.
#[derive(Clone, Copy, Debug, PartialEq, Hash, Eq)]
pub enum StackProtector {
    /// Disable stack canary generation.
    None,

    /// On LLVM, mark all generated LLVM functions with the `ssp` attribute (see
    /// llvm/docs/LangRef.rst). This triggers stack canary generation in
    /// functions which contain an array of a byte-sized type with more than
    /// eight elements.
    Basic,

    /// On LLVM, mark all generated LLVM functions with the `sspstrong`
    /// attribute (see llvm/docs/LangRef.rst). This triggers stack canary
    /// generation in functions which either contain an array, or which take
    /// the address of a local variable.
    Strong,

    /// Generate stack canaries in all functions.
    All,
}

impl StackProtector {
    fn as_str(&self) -> &'static str {
        match self {
            StackProtector::None => "none",
            StackProtector::Basic => "basic",
            StackProtector::Strong => "strong",
            StackProtector::All => "all",
        }
    }
}

impl FromStr for StackProtector {
    type Err = ();

    fn from_str(s: &str) -> Result<StackProtector, ()> {
        Ok(match s {
            "none" => StackProtector::None,
            "basic" => StackProtector::Basic,
            "strong" => StackProtector::Strong,
            "all" => StackProtector::All,
            _ => return Err(()),
        })
    }
}

impl fmt::Display for StackProtector {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        f.write_str(self.as_str())
    }
}

macro_rules! supported_targets {
    ( $(($triple:literal, $module:ident),)+ ) => {
        $(mod $module;)+

        /// List of supported targets
        pub const TARGETS: &[&str] = &[$($triple),+];

        fn load_builtin(target: &str) -> Option<Target> {
            let mut t = match target {
                $( $triple => $module::target(), )+
                _ => return None,
            };
            t.is_builtin = true;
            debug!("got builtin target: {:?}", t);
            Some(t)
        }

        #[cfg(test)]
        mod tests {
            mod tests_impl;

            // Cannot put this into a separate file without duplication, make an exception.
            $(
                #[test] // `#[test]`
                fn $module() {
                    tests_impl::test_target(super::$module::target());
                }
            )+
        }
    };
}

supported_targets! {
    ("x86_64-unknown-linux-gnu", x86_64_unknown_linux_gnu),
    ("x86_64-unknown-linux-gnux32", x86_64_unknown_linux_gnux32),
    ("i686-unknown-linux-gnu", i686_unknown_linux_gnu),
    ("i586-unknown-linux-gnu", i586_unknown_linux_gnu),
    ("loongarch64-unknown-linux-gnu", loongarch64_unknown_linux_gnu),
    ("m68k-unknown-linux-gnu", m68k_unknown_linux_gnu),
    ("csky-unknown-linux-gnuabiv2", csky_unknown_linux_gnuabiv2),
    ("mips-unknown-linux-gnu", mips_unknown_linux_gnu),
    ("mips64-unknown-linux-gnuabi64", mips64_unknown_linux_gnuabi64),
    ("mips64el-unknown-linux-gnuabi64", mips64el_unknown_linux_gnuabi64),
    ("mipsisa32r6-unknown-linux-gnu", mipsisa32r6_unknown_linux_gnu),
    ("mipsisa32r6el-unknown-linux-gnu", mipsisa32r6el_unknown_linux_gnu),
    ("mipsisa64r6-unknown-linux-gnuabi64", mipsisa64r6_unknown_linux_gnuabi64),
    ("mipsisa64r6el-unknown-linux-gnuabi64", mipsisa64r6el_unknown_linux_gnuabi64),
    ("mipsel-unknown-linux-gnu", mipsel_unknown_linux_gnu),
    ("powerpc-unknown-linux-gnu", powerpc_unknown_linux_gnu),
    ("powerpc-unknown-linux-gnuspe", powerpc_unknown_linux_gnuspe),
    ("powerpc-unknown-linux-musl", powerpc_unknown_linux_musl),
    ("powerpc64-ibm-aix", powerpc64_ibm_aix),
    ("powerpc64-unknown-linux-gnu", powerpc64_unknown_linux_gnu),
    ("powerpc64-unknown-linux-musl", powerpc64_unknown_linux_musl),
    ("powerpc64le-unknown-linux-gnu", powerpc64le_unknown_linux_gnu),
    ("powerpc64le-unknown-linux-musl", powerpc64le_unknown_linux_musl),
    ("s390x-unknown-linux-gnu", s390x_unknown_linux_gnu),
    ("s390x-unknown-linux-musl", s390x_unknown_linux_musl),
    ("sparc-unknown-linux-gnu", sparc_unknown_linux_gnu),
    ("sparc64-unknown-linux-gnu", sparc64_unknown_linux_gnu),
    ("arm-unknown-linux-gnueabi", arm_unknown_linux_gnueabi),
    ("arm-unknown-linux-gnueabihf", arm_unknown_linux_gnueabihf),
    ("armeb-unknown-linux-gnueabi", armeb_unknown_linux_gnueabi),
    ("arm-unknown-linux-musleabi", arm_unknown_linux_musleabi),
    ("arm-unknown-linux-musleabihf", arm_unknown_linux_musleabihf),
    ("armv4t-unknown-linux-gnueabi", armv4t_unknown_linux_gnueabi),
    ("armv5te-unknown-linux-gnueabi", armv5te_unknown_linux_gnueabi),
    ("armv5te-unknown-linux-musleabi", armv5te_unknown_linux_musleabi),
    ("armv5te-unknown-linux-uclibceabi", armv5te_unknown_linux_uclibceabi),
    ("armv7-unknown-linux-gnueabi", armv7_unknown_linux_gnueabi),
    ("armv7-unknown-linux-gnueabihf", armv7_unknown_linux_gnueabihf),
    ("thumbv7neon-unknown-linux-gnueabihf", thumbv7neon_unknown_linux_gnueabihf),
    ("thumbv7neon-unknown-linux-musleabihf", thumbv7neon_unknown_linux_musleabihf),
    ("armv7-unknown-linux-musleabi", armv7_unknown_linux_musleabi),
    ("armv7-unknown-linux-musleabihf", armv7_unknown_linux_musleabihf),
    ("aarch64-unknown-linux-gnu", aarch64_unknown_linux_gnu),
    ("aarch64-unknown-linux-musl", aarch64_unknown_linux_musl),
    ("x86_64-unknown-linux-musl", x86_64_unknown_linux_musl),
    ("i686-unknown-linux-musl", i686_unknown_linux_musl),
    ("i586-unknown-linux-musl", i586_unknown_linux_musl),
    ("mips-unknown-linux-musl", mips_unknown_linux_musl),
    ("mipsel-unknown-linux-musl", mipsel_unknown_linux_musl),
    ("mips64-unknown-linux-muslabi64", mips64_unknown_linux_muslabi64),
    ("mips64el-unknown-linux-muslabi64", mips64el_unknown_linux_muslabi64),
    ("hexagon-unknown-linux-musl", hexagon_unknown_linux_musl),

    ("mips-unknown-linux-uclibc", mips_unknown_linux_uclibc),
    ("mipsel-unknown-linux-uclibc", mipsel_unknown_linux_uclibc),

    ("i686-linux-android", i686_linux_android),
    ("x86_64-linux-android", x86_64_linux_android),
    ("arm-linux-androideabi", arm_linux_androideabi),
    ("armv7-linux-androideabi", armv7_linux_androideabi),
    ("thumbv7neon-linux-androideabi", thumbv7neon_linux_androideabi),
    ("aarch64-linux-android", aarch64_linux_android),
    ("riscv64-linux-android", riscv64_linux_android),

    ("aarch64-unknown-freebsd", aarch64_unknown_freebsd),
    ("armv6-unknown-freebsd", armv6_unknown_freebsd),
    ("armv7-unknown-freebsd", armv7_unknown_freebsd),
    ("i686-unknown-freebsd", i686_unknown_freebsd),
    ("powerpc-unknown-freebsd", powerpc_unknown_freebsd),
    ("powerpc64-unknown-freebsd", powerpc64_unknown_freebsd),
    ("powerpc64le-unknown-freebsd", powerpc64le_unknown_freebsd),
    ("riscv64gc-unknown-freebsd", riscv64gc_unknown_freebsd),
    ("x86_64-unknown-freebsd", x86_64_unknown_freebsd),

    ("x86_64-unknown-dragonfly", x86_64_unknown_dragonfly),

    ("aarch64-unknown-openbsd", aarch64_unknown_openbsd),
    ("i686-unknown-openbsd", i686_unknown_openbsd),
    ("powerpc-unknown-openbsd", powerpc_unknown_openbsd),
    ("powerpc64-unknown-openbsd", powerpc64_unknown_openbsd),
    ("riscv64gc-unknown-openbsd", riscv64gc_unknown_openbsd),
    ("sparc64-unknown-openbsd", sparc64_unknown_openbsd),
    ("x86_64-unknown-openbsd", x86_64_unknown_openbsd),

    ("aarch64-unknown-netbsd", aarch64_unknown_netbsd),
    ("aarch64_be-unknown-netbsd", aarch64_be_unknown_netbsd),
    ("armv6-unknown-netbsd-eabihf", armv6_unknown_netbsd_eabihf),
    ("armv7-unknown-netbsd-eabihf", armv7_unknown_netbsd_eabihf),
    ("i686-unknown-netbsd", i686_unknown_netbsd),
    ("powerpc-unknown-netbsd", powerpc_unknown_netbsd),
    ("riscv64gc-unknown-netbsd", riscv64gc_unknown_netbsd),
    ("sparc64-unknown-netbsd", sparc64_unknown_netbsd),
    ("x86_64-unknown-netbsd", x86_64_unknown_netbsd),

    ("i686-unknown-haiku", i686_unknown_haiku),
    ("x86_64-unknown-haiku", x86_64_unknown_haiku),

    ("i686-unknown-hurd-gnu", i686_unknown_hurd_gnu),

    ("aarch64-apple-darwin", aarch64_apple_darwin),
    ("x86_64-apple-darwin", x86_64_apple_darwin),
    ("x86_64h-apple-darwin", x86_64h_apple_darwin),
    ("i686-apple-darwin", i686_apple_darwin),

    // FIXME(#106649): Remove aarch64-fuchsia in favor of aarch64-unknown-fuchsia
    ("aarch64-fuchsia", aarch64_fuchsia),
    ("aarch64-unknown-fuchsia", aarch64_unknown_fuchsia),
    ("riscv64gc-unknown-fuchsia", riscv64gc_unknown_fuchsia),
    // FIXME(#106649): Remove x86_64-fuchsia in favor of x86_64-unknown-fuchsia
    ("x86_64-fuchsia", x86_64_fuchsia),
    ("x86_64-unknown-fuchsia", x86_64_unknown_fuchsia),

    ("avr-unknown-gnu-atmega328", avr_unknown_gnu_atmega328),

    ("x86_64-unknown-l4re-uclibc", x86_64_unknown_l4re_uclibc),

    ("aarch64-unknown-redox", aarch64_unknown_redox),
    ("x86_64-unknown-redox", x86_64_unknown_redox),

    ("i386-apple-ios", i386_apple_ios),
    ("x86_64-apple-ios", x86_64_apple_ios),
    ("aarch64-apple-ios", aarch64_apple_ios),
    ("armv7s-apple-ios", armv7s_apple_ios),
    ("x86_64-apple-ios-macabi", x86_64_apple_ios_macabi),
    ("aarch64-apple-ios-macabi", aarch64_apple_ios_macabi),
    ("aarch64-apple-ios-sim", aarch64_apple_ios_sim),
    ("aarch64-apple-tvos", aarch64_apple_tvos),
    ("x86_64-apple-tvos", x86_64_apple_tvos),

    ("armv7k-apple-watchos", armv7k_apple_watchos),
    ("arm64_32-apple-watchos", arm64_32_apple_watchos),
    ("x86_64-apple-watchos-sim", x86_64_apple_watchos_sim),
    ("aarch64-apple-watchos-sim", aarch64_apple_watchos_sim),

    ("armebv7r-none-eabi", armebv7r_none_eabi),
    ("armebv7r-none-eabihf", armebv7r_none_eabihf),
    ("armv7r-none-eabi", armv7r_none_eabi),
    ("armv7r-none-eabihf", armv7r_none_eabihf),

    ("x86_64-pc-solaris", x86_64_pc_solaris),
    ("x86_64-sun-solaris", x86_64_sun_solaris),
    ("sparcv9-sun-solaris", sparcv9_sun_solaris),

    ("x86_64-unknown-illumos", x86_64_unknown_illumos),

    ("x86_64-pc-windows-gnu", x86_64_pc_windows_gnu),
    ("i686-pc-windows-gnu", i686_pc_windows_gnu),
    ("i686-uwp-windows-gnu", i686_uwp_windows_gnu),
    ("x86_64-uwp-windows-gnu", x86_64_uwp_windows_gnu),

    ("aarch64-pc-windows-gnullvm", aarch64_pc_windows_gnullvm),
    ("i686-pc-windows-gnullvm", i686_pc_windows_gnullvm),
    ("x86_64-pc-windows-gnullvm", x86_64_pc_windows_gnullvm),

    ("aarch64-pc-windows-msvc", aarch64_pc_windows_msvc),
    ("aarch64-uwp-windows-msvc", aarch64_uwp_windows_msvc),
    ("x86_64-pc-windows-msvc", x86_64_pc_windows_msvc),
    ("x86_64-uwp-windows-msvc", x86_64_uwp_windows_msvc),
    ("i686-pc-windows-msvc", i686_pc_windows_msvc),
    ("i686-uwp-windows-msvc", i686_uwp_windows_msvc),
    ("i586-pc-windows-msvc", i586_pc_windows_msvc),
    ("thumbv7a-pc-windows-msvc", thumbv7a_pc_windows_msvc),
    ("thumbv7a-uwp-windows-msvc", thumbv7a_uwp_windows_msvc),

    ("asmjs-unknown-emscripten", asmjs_unknown_emscripten),
    ("wasm32-unknown-emscripten", wasm32_unknown_emscripten),
    ("wasm32-unknown-unknown", wasm32_unknown_unknown),
    ("wasm32-wasi", wasm32_wasi),
    ("wasm32-wasi-preview1-threads", wasm32_wasi_preview1_threads),
    ("wasm64-unknown-unknown", wasm64_unknown_unknown),

    ("thumbv6m-none-eabi", thumbv6m_none_eabi),
    ("thumbv7m-none-eabi", thumbv7m_none_eabi),
    ("thumbv7em-none-eabi", thumbv7em_none_eabi),
    ("thumbv7em-none-eabihf", thumbv7em_none_eabihf),
    ("thumbv8m.base-none-eabi", thumbv8m_base_none_eabi),
    ("thumbv8m.main-none-eabi", thumbv8m_main_none_eabi),
    ("thumbv8m.main-none-eabihf", thumbv8m_main_none_eabihf),

    ("armv7a-none-eabi", armv7a_none_eabi),
    ("armv7a-none-eabihf", armv7a_none_eabihf),

    ("msp430-none-elf", msp430_none_elf),

    ("aarch64-unknown-hermit", aarch64_unknown_hermit),
    ("riscv64gc-unknown-hermit", riscv64gc_unknown_hermit),
    ("x86_64-unknown-hermit", x86_64_unknown_hermit),

    ("x86_64-unikraft-linux-musl", x86_64_unikraft_linux_musl),

    ("riscv32i-unknown-none-elf", riscv32i_unknown_none_elf),
    ("riscv32im-unknown-none-elf", riscv32im_unknown_none_elf),
    ("riscv32imc-unknown-none-elf", riscv32imc_unknown_none_elf),
    ("riscv32imc-esp-espidf", riscv32imc_esp_espidf),
    ("riscv32imac-esp-espidf", riscv32imac_esp_espidf),
    ("riscv32imac-unknown-none-elf", riscv32imac_unknown_none_elf),
    ("riscv32imac-unknown-xous-elf", riscv32imac_unknown_xous_elf),
    ("riscv32gc-unknown-linux-gnu", riscv32gc_unknown_linux_gnu),
    ("riscv32gc-unknown-linux-musl", riscv32gc_unknown_linux_musl),
    ("riscv64imac-unknown-none-elf", riscv64imac_unknown_none_elf),
    ("riscv64gc-unknown-none-elf", riscv64gc_unknown_none_elf),
    ("riscv64gc-unknown-linux-gnu", riscv64gc_unknown_linux_gnu),
    ("riscv64gc-unknown-linux-musl", riscv64gc_unknown_linux_musl),

    ("sparc-unknown-none-elf", sparc_unknown_none_elf),

    ("loongarch64-unknown-none", loongarch64_unknown_none),
    ("loongarch64-unknown-none-softfloat", loongarch64_unknown_none_softfloat),

    ("aarch64-unknown-none", aarch64_unknown_none),
    ("aarch64-unknown-none-softfloat", aarch64_unknown_none_softfloat),

    ("x86_64-fortanix-unknown-sgx", x86_64_fortanix_unknown_sgx),

    ("x86_64-unknown-uefi", x86_64_unknown_uefi),
    ("i686-unknown-uefi", i686_unknown_uefi),
    ("aarch64-unknown-uefi", aarch64_unknown_uefi),

    ("nvptx64-nvidia-cuda", nvptx64_nvidia_cuda),

    ("i686-wrs-vxworks", i686_wrs_vxworks),
    ("x86_64-wrs-vxworks", x86_64_wrs_vxworks),
    ("armv7-wrs-vxworks-eabihf", armv7_wrs_vxworks_eabihf),
    ("aarch64-wrs-vxworks", aarch64_wrs_vxworks),
    ("powerpc-wrs-vxworks", powerpc_wrs_vxworks),
    ("powerpc-wrs-vxworks-spe", powerpc_wrs_vxworks_spe),
    ("powerpc64-wrs-vxworks", powerpc64_wrs_vxworks),

    ("aarch64-kmc-solid_asp3", aarch64_kmc_solid_asp3),
    ("armv7a-kmc-solid_asp3-eabi", armv7a_kmc_solid_asp3_eabi),
    ("armv7a-kmc-solid_asp3-eabihf", armv7a_kmc_solid_asp3_eabihf),

    ("mipsel-sony-psp", mipsel_sony_psp),
    ("mipsel-sony-psx", mipsel_sony_psx),
    ("mipsel-unknown-none", mipsel_unknown_none),
    ("thumbv4t-none-eabi", thumbv4t_none_eabi),
    ("armv4t-none-eabi", armv4t_none_eabi),
    ("thumbv5te-none-eabi", thumbv5te_none_eabi),
    ("armv5te-none-eabi", armv5te_none_eabi),

    ("aarch64_be-unknown-linux-gnu", aarch64_be_unknown_linux_gnu),
    ("aarch64-unknown-linux-gnu_ilp32", aarch64_unknown_linux_gnu_ilp32),
    ("aarch64_be-unknown-linux-gnu_ilp32", aarch64_be_unknown_linux_gnu_ilp32),

    ("bpfeb-unknown-none", bpfeb_unknown_none),
    ("bpfel-unknown-none", bpfel_unknown_none),

    ("armv6k-nintendo-3ds", armv6k_nintendo_3ds),

    ("aarch64-nintendo-switch-freestanding", aarch64_nintendo_switch_freestanding),

    ("armv7-sony-vita-newlibeabihf", armv7_sony_vita_newlibeabihf),

    ("armv7-unknown-linux-uclibceabi", armv7_unknown_linux_uclibceabi),
    ("armv7-unknown-linux-uclibceabihf", armv7_unknown_linux_uclibceabihf),

    ("x86_64-unknown-none", x86_64_unknown_none),

    ("aarch64-unknown-teeos", aarch64_unknown_teeos),

    ("mips64-openwrt-linux-musl", mips64_openwrt_linux_musl),

    ("aarch64-unknown-nto-qnx710", aarch64_unknown_nto_qnx_710),
    ("x86_64-pc-nto-qnx710", x86_64_pc_nto_qnx710),
    ("i586-pc-nto-qnx700", i586_pc_nto_qnx700),

    ("aarch64-unknown-linux-ohos", aarch64_unknown_linux_ohos),
    ("armv7-unknown-linux-ohos", armv7_unknown_linux_ohos),
    ("x86_64-unknown-linux-ohos", x86_64_unknown_linux_ohos),
}

/// Cow-Vec-Str: Cow<'static, [Cow<'static, str>]>
macro_rules! cvs {
    () => {
        ::std::borrow::Cow::Borrowed(&[])
    };
    ($($x:expr),+ $(,)?) => {
        ::std::borrow::Cow::Borrowed(&[
            $(
                ::std::borrow::Cow::Borrowed($x),
            )*
        ])
    };
}

pub(crate) use cvs;

/// Warnings encountered when parsing the target `json`.
///
/// Includes fields that weren't recognized and fields that don't have the expected type.
#[derive(Debug, PartialEq)]
pub struct TargetWarnings {
    unused_fields: Vec<String>,
    incorrect_type: Vec<String>,
}

impl TargetWarnings {
    pub fn empty() -> Self {
        Self { unused_fields: Vec::new(), incorrect_type: Vec::new() }
    }

    pub fn warning_messages(&self) -> Vec<String> {
        let mut warnings = vec![];
        if !self.unused_fields.is_empty() {
            warnings.push(format!(
                "target json file contains unused fields: {}",
                self.unused_fields.join(", ")
            ));
        }
        if !self.incorrect_type.is_empty() {
            warnings.push(format!(
                "target json file contains fields whose value doesn't have the correct json type: {}",
                self.incorrect_type.join(", ")
            ));
        }
        warnings
    }
}

/// Everything `rustc` knows about how to compile for a specific target.
///
/// Every field here must be specified, and has no default value.
#[derive(PartialEq, Clone, Debug)]
pub struct Target {
    /// Target triple to pass to LLVM.
    pub llvm_target: StaticCow<str>,
    /// Number of bits in a pointer. Influences the `target_pointer_width` `cfg` variable.
    pub pointer_width: u32,
    /// Architecture to use for ABI considerations. Valid options include: "x86",
    /// "x86_64", "arm", "aarch64", "mips", "powerpc", "powerpc64", and others.
    pub arch: StaticCow<str>,
    /// [Data layout](https://llvm.org/docs/LangRef.html#data-layout) to pass to LLVM.
    pub data_layout: StaticCow<str>,
    /// Optional settings with defaults.
    pub options: TargetOptions,
}

impl Target {
    pub fn parse_data_layout(&self) -> Result<TargetDataLayout, TargetDataLayoutErrors<'_>> {
        let mut dl = TargetDataLayout::parse_from_llvm_datalayout_string(&self.data_layout)?;

        // Perform consistency checks against the Target information.
        if dl.endian != self.endian {
            return Err(TargetDataLayoutErrors::InconsistentTargetArchitecture {
                dl: dl.endian.as_str(),
                target: self.endian.as_str(),
            });
        }

        let target_pointer_width: u64 = self.pointer_width.into();
        if dl.pointer_size.bits() != target_pointer_width {
            return Err(TargetDataLayoutErrors::InconsistentTargetPointerWidth {
                pointer_size: dl.pointer_size.bits(),
                target: self.pointer_width,
            });
        }

        dl.c_enum_min_size = self
            .c_enum_min_bits
            .map_or_else(
                || {
                    self.c_int_width
                        .parse()
                        .map_err(|_| String::from("failed to parse c_int_width"))
                },
                Ok,
            )
            .and_then(|i| Integer::from_size(Size::from_bits(i)))
            .map_err(|err| TargetDataLayoutErrors::InvalidBitsSize { err })?;

        Ok(dl)
    }
}

pub trait HasTargetSpec {
    fn target_spec(&self) -> &Target;
}

impl HasTargetSpec for Target {
    #[inline]
    fn target_spec(&self) -> &Target {
        self
    }
}

type StaticCow<T> = Cow<'static, T>;

/// Optional aspects of a target specification.
///
/// This has an implementation of `Default`, see each field for what the default is. In general,
/// these try to take "minimal defaults" that don't assume anything about the runtime they run in.
///
/// `TargetOptions` as a separate structure is mostly an implementation detail of `Target`
/// construction, all its fields logically belong to `Target` and available from `Target`
/// through `Deref` impls.
#[derive(PartialEq, Clone, Debug)]
pub struct TargetOptions {
    /// Whether the target is built-in or loaded from a custom target specification.
    pub is_builtin: bool,

    /// Used as the `target_endian` `cfg` variable. Defaults to little endian.
    pub endian: Endian,
    /// Width of c_int type. Defaults to "32".
    pub c_int_width: StaticCow<str>,
    /// OS name to use for conditional compilation (`target_os`). Defaults to "none".
    /// "none" implies a bare metal target without `std` library.
    /// A couple of targets having `std` also use "unknown" as an `os` value,
    /// but they are exceptions.
    pub os: StaticCow<str>,
    /// Environment name to use for conditional compilation (`target_env`). Defaults to "".
    pub env: StaticCow<str>,
    /// ABI name to distinguish multiple ABIs on the same OS and architecture. For instance, `"eabi"`
    /// or `"eabihf"`. Defaults to "".
    pub abi: StaticCow<str>,
    /// Vendor name to use for conditional compilation (`target_vendor`). Defaults to "unknown".
    pub vendor: StaticCow<str>,

    /// Linker to invoke
    pub linker: Option<StaticCow<str>>,
    /// Default linker flavor used if `-C linker-flavor` or `-C linker` are not passed
    /// on the command line. Defaults to `LinkerFlavor::Gnu(Cc::Yes, Lld::No)`.
    pub linker_flavor: LinkerFlavor,
    linker_flavor_json: LinkerFlavorCli,
    lld_flavor_json: LldFlavor,
    linker_is_gnu_json: bool,

    /// Objects to link before and after all other object code.
    pub pre_link_objects: CrtObjects,
    pub post_link_objects: CrtObjects,
    /// Same as `(pre|post)_link_objects`, but when self-contained linking mode is enabled.
    pub pre_link_objects_self_contained: CrtObjects,
    pub post_link_objects_self_contained: CrtObjects,
    pub link_self_contained: LinkSelfContainedDefault,

    /// Linker arguments that are passed *before* any user-defined libraries.
    pub pre_link_args: LinkArgs,
    pre_link_args_json: LinkArgsCli,
    /// Linker arguments that are unconditionally passed after any
    /// user-defined but before post-link objects. Standard platform
    /// libraries that should be always be linked to, usually go here.
    pub late_link_args: LinkArgs,
    late_link_args_json: LinkArgsCli,
    /// Linker arguments used in addition to `late_link_args` if at least one
    /// Rust dependency is dynamically linked.
    pub late_link_args_dynamic: LinkArgs,
    late_link_args_dynamic_json: LinkArgsCli,
    /// Linker arguments used in addition to `late_link_args` if all Rust
    /// dependencies are statically linked.
    pub late_link_args_static: LinkArgs,
    late_link_args_static_json: LinkArgsCli,
    /// Linker arguments that are unconditionally passed *after* any
    /// user-defined libraries.
    pub post_link_args: LinkArgs,
    post_link_args_json: LinkArgsCli,

    /// Optional link script applied to `dylib` and `executable` crate types.
    /// This is a string containing the script, not a path. Can only be applied
    /// to linkers where linker flavor matches `LinkerFlavor::Gnu(..)`.
    pub link_script: Option<StaticCow<str>>,
    /// Environment variables to be set for the linker invocation.
    pub link_env: StaticCow<[(StaticCow<str>, StaticCow<str>)]>,
    /// Environment variables to be removed for the linker invocation.
    pub link_env_remove: StaticCow<[StaticCow<str>]>,

    /// Extra arguments to pass to the external assembler (when used)
    pub asm_args: StaticCow<[StaticCow<str>]>,

    /// Default CPU to pass to LLVM. Corresponds to `llc -mcpu=$cpu`. Defaults
    /// to "generic".
    pub cpu: StaticCow<str>,
    /// Default target features to pass to LLVM. These features will *always* be
    /// passed, and cannot be disabled even via `-C`. Corresponds to `llc
    /// -mattr=$features`.
    pub features: StaticCow<str>,
    /// Whether dynamic linking is available on this target. Defaults to false.
    pub dynamic_linking: bool,
    /// Whether dynamic linking can export TLS globals. Defaults to true.
    pub dll_tls_export: bool,
    /// If dynamic linking is available, whether only cdylibs are supported.
    pub only_cdylib: bool,
    /// Whether executables are available on this target. Defaults to true.
    pub executables: bool,
    /// Relocation model to use in object file. Corresponds to `llc
    /// -relocation-model=$relocation_model`. Defaults to `Pic`.
    pub relocation_model: RelocModel,
    /// Code model to use. Corresponds to `llc -code-model=$code_model`.
    /// Defaults to `None` which means "inherited from the base LLVM target".
    pub code_model: Option<CodeModel>,
    /// TLS model to use. Options are "global-dynamic" (default), "local-dynamic", "initial-exec"
    /// and "local-exec". This is similar to the -ftls-model option in GCC/Clang.
    pub tls_model: TlsModel,
    /// Do not emit code that uses the "red zone", if the ABI has one. Defaults to false.
    pub disable_redzone: bool,
    /// Frame pointer mode for this target. Defaults to `MayOmit`.
    pub frame_pointer: FramePointer,
    /// Emit each function in its own section. Defaults to true.
    pub function_sections: bool,
    /// String to prepend to the name of every dynamic library. Defaults to "lib".
    pub dll_prefix: StaticCow<str>,
    /// String to append to the name of every dynamic library. Defaults to ".so".
    pub dll_suffix: StaticCow<str>,
    /// String to append to the name of every executable.
    pub exe_suffix: StaticCow<str>,
    /// String to prepend to the name of every static library. Defaults to "lib".
    pub staticlib_prefix: StaticCow<str>,
    /// String to append to the name of every static library. Defaults to ".a".
    pub staticlib_suffix: StaticCow<str>,
    /// Values of the `target_family` cfg set for this target.
    ///
    /// Common options are: "unix", "windows". Defaults to no families.
    ///
    /// See <https://doc.rust-lang.org/reference/conditional-compilation.html#target_family>.
    pub families: StaticCow<[StaticCow<str>]>,
    /// Whether the target toolchain's ABI supports returning small structs as an integer.
    pub abi_return_struct_as_int: bool,
    /// Whether the target toolchain is like AIX's. Linker options on AIX are special and it uses
    /// XCOFF as binary format. Defaults to false.
    pub is_like_aix: bool,
    /// Whether the target toolchain is like macOS's. Only useful for compiling against iOS/macOS,
    /// in particular running dsymutil and some other stuff like `-dead_strip`. Defaults to false.
    /// Also indiates whether to use Apple-specific ABI changes, such as extending function
    /// parameters to 32-bits.
    pub is_like_osx: bool,
    /// Whether the target toolchain is like Solaris's.
    /// Only useful for compiling against Illumos/Solaris,
    /// as they have a different set of linker flags. Defaults to false.
    pub is_like_solaris: bool,
    /// Whether the target is like Windows.
    /// This is a combination of several more specific properties represented as a single flag:
    ///   - The target uses a Windows ABI,
    ///   - uses PE/COFF as a format for object code,
    ///   - uses Windows-style dllexport/dllimport for shared libraries,
    ///   - uses import libraries and .def files for symbol exports,
    ///   - executables support setting a subsystem.
    pub is_like_windows: bool,
    /// Whether the target is like MSVC.
    /// This is a combination of several more specific properties represented as a single flag:
    ///   - The target has all the properties from `is_like_windows`
    ///     (for in-tree targets "is_like_msvc ⇒ is_like_windows" is ensured by a unit test),
    ///   - has some MSVC-specific Windows ABI properties,
    ///   - uses a link.exe-like linker,
    ///   - uses CodeView/PDB for debuginfo and natvis for its visualization,
    ///   - uses SEH-based unwinding,
    ///   - supports control flow guard mechanism.
    pub is_like_msvc: bool,
    /// Whether a target toolchain is like WASM.
    pub is_like_wasm: bool,
    /// Whether a target toolchain is like Android, implying a Linux kernel and a Bionic libc
    pub is_like_android: bool,
    /// Default supported version of DWARF on this platform.
    /// Useful because some platforms (osx, bsd) only want up to DWARF2.
    pub default_dwarf_version: u32,
    /// The MinGW toolchain has a known issue that prevents it from correctly
    /// handling COFF object files with more than 2<sup>15</sup> sections. Since each weak
    /// symbol needs its own COMDAT section, weak linkage implies a large
    /// number sections that easily exceeds the given limit for larger
    /// codebases. Consequently we want a way to disallow weak linkage on some
    /// platforms.
    pub allows_weak_linkage: bool,
    /// Whether the linker support rpaths or not. Defaults to false.
    pub has_rpath: bool,
    /// Whether to disable linking to the default libraries, typically corresponds
    /// to `-nodefaultlibs`. Defaults to true.
    pub no_default_libraries: bool,
    /// Dynamically linked executables can be compiled as position independent
    /// if the default relocation model of position independent code is not
    /// changed. This is a requirement to take advantage of ASLR, as otherwise
    /// the functions in the executable are not randomized and can be used
    /// during an exploit of a vulnerability in any code.
    pub position_independent_executables: bool,
    /// Executables that are both statically linked and position-independent are supported.
    pub static_position_independent_executables: bool,
    /// Determines if the target always requires using the PLT for indirect
    /// library calls or not. This controls the default value of the `-Z plt` flag.
    pub plt_by_default: bool,
    /// Either partial, full, or off. Full RELRO makes the dynamic linker
    /// resolve all symbols at startup and marks the GOT read-only before
    /// starting the program, preventing overwriting the GOT.
    pub relro_level: RelroLevel,
    /// Format that archives should be emitted in. This affects whether we use
    /// LLVM to assemble an archive or fall back to the system linker, and
    /// currently only "gnu" is used to fall into LLVM. Unknown strings cause
    /// the system linker to be used.
    pub archive_format: StaticCow<str>,
    /// Is asm!() allowed? Defaults to true.
    pub allow_asm: bool,
    /// Whether the runtime startup code requires the `main` function be passed
    /// `argc` and `argv` values.
    pub main_needs_argc_argv: bool,

    /// Flag indicating whether #[thread_local] is available for this target.
    pub has_thread_local: bool,
    /// This is mainly for easy compatibility with emscripten.
    /// If we give emcc .o files that are actually .bc files it
    /// will 'just work'.
    pub obj_is_bitcode: bool,
    /// Whether the target requires that emitted object code includes bitcode.
    pub forces_embed_bitcode: bool,
    /// Content of the LLVM cmdline section associated with embedded bitcode.
    pub bitcode_llvm_cmdline: StaticCow<str>,

    /// Don't use this field; instead use the `.min_atomic_width()` method.
    pub min_atomic_width: Option<u64>,

    /// Don't use this field; instead use the `.max_atomic_width()` method.
    pub max_atomic_width: Option<u64>,

    /// Whether the target supports atomic CAS operations natively
    pub atomic_cas: bool,

    /// Panic strategy: "unwind" or "abort"
    pub panic_strategy: PanicStrategy,

    /// Whether or not linking dylibs to a static CRT is allowed.
    pub crt_static_allows_dylibs: bool,
    /// Whether or not the CRT is statically linked by default.
    pub crt_static_default: bool,
    /// Whether or not crt-static is respected by the compiler (or is a no-op).
    pub crt_static_respected: bool,

    /// The implementation of stack probes to use.
    pub stack_probes: StackProbeType,

    /// The minimum alignment for global symbols.
    pub min_global_align: Option<u64>,

    /// Default number of codegen units to use in debug mode
    pub default_codegen_units: Option<u64>,

    /// Whether to generate trap instructions in places where optimization would
    /// otherwise produce control flow that falls through into unrelated memory.
    pub trap_unreachable: bool,

    /// This target requires everything to be compiled with LTO to emit a final
    /// executable, aka there is no native linker for this target.
    pub requires_lto: bool,

    /// This target has no support for threads.
    pub singlethread: bool,

    /// Whether library functions call lowering/optimization is disabled in LLVM
    /// for this target unconditionally.
    pub no_builtins: bool,

    /// The default visibility for symbols in this target should be "hidden"
    /// rather than "default"
    pub default_hidden_visibility: bool,

    /// Whether a .debug_gdb_scripts section will be added to the output object file
    pub emit_debug_gdb_scripts: bool,

    /// Whether or not to unconditionally `uwtable` attributes on functions,
    /// typically because the platform needs to unwind for things like stack
    /// unwinders.
    pub requires_uwtable: bool,

    /// Whether or not to emit `uwtable` attributes on functions if `-C force-unwind-tables`
    /// is not specified and `uwtable` is not required on this target.
    pub default_uwtable: bool,

    /// Whether or not SIMD types are passed by reference in the Rust ABI,
    /// typically required if a target can be compiled with a mixed set of
    /// target features. This is `true` by default, and `false` for targets like
    /// wasm32 where the whole program either has simd or not.
    pub simd_types_indirect: bool,

    /// Pass a list of symbol which should be exported in the dylib to the linker.
    pub limit_rdylib_exports: bool,

    /// If set, have the linker export exactly these symbols, instead of using
    /// the usual logic to figure this out from the crate itself.
    pub override_export_symbols: Option<StaticCow<[StaticCow<str>]>>,

    /// Determines how or whether the MergeFunctions LLVM pass should run for
    /// this target. Either "disabled", "trampolines", or "aliases".
    /// The MergeFunctions pass is generally useful, but some targets may need
    /// to opt out. The default is "aliases".
    ///
    /// Workaround for: <https://github.com/rust-lang/rust/issues/57356>
    pub merge_functions: MergeFunctions,

    /// Use platform dependent mcount function
    pub mcount: StaticCow<str>,

    /// Use LLVM intrinsic for mcount function name
    pub llvm_mcount_intrinsic: Option<StaticCow<str>>,

    /// LLVM ABI name, corresponds to the '-mabi' parameter available in multilib C compilers
    pub llvm_abiname: StaticCow<str>,

    /// Whether or not RelaxElfRelocation flag will be passed to the linker
    pub relax_elf_relocations: bool,

    /// Additional arguments to pass to LLVM, similar to the `-C llvm-args` codegen option.
    pub llvm_args: StaticCow<[StaticCow<str>]>,

    /// Whether to use legacy .ctors initialization hooks rather than .init_array. Defaults
    /// to false (uses .init_array).
    pub use_ctors_section: bool,

    /// Whether the linker is instructed to add a `GNU_EH_FRAME` ELF header
    /// used to locate unwinding information is passed
    /// (only has effect if the linker is `ld`-like).
    pub eh_frame_header: bool,

    /// Is true if the target is an ARM architecture using thumb v1 which allows for
    /// thumb and arm interworking.
    pub has_thumb_interworking: bool,

    /// Which kind of debuginfo is used by this target?
    pub debuginfo_kind: DebuginfoKind,
    /// How to handle split debug information, if at all. Specifying `None` has
    /// target-specific meaning.
    pub split_debuginfo: SplitDebuginfo,
    /// Which kinds of split debuginfo are supported by the target?
    pub supported_split_debuginfo: StaticCow<[SplitDebuginfo]>,

    /// The sanitizers supported by this target
    ///
    /// Note that the support here is at a codegen level. If the machine code with sanitizer
    /// enabled can generated on this target, but the necessary supporting libraries are not
    /// distributed with the target, the sanitizer should still appear in this list for the target.
    pub supported_sanitizers: SanitizerSet,

    /// If present it's a default value to use for adjusting the C ABI.
    pub default_adjusted_cabi: Option<Abi>,

    /// Minimum number of bits in #[repr(C)] enum. Defaults to the size of c_int
    pub c_enum_min_bits: Option<u64>,

    /// Whether or not the DWARF `.debug_aranges` section should be generated.
    pub generate_arange_section: bool,

    /// Whether the target supports stack canary checks. `true` by default,
    /// since this is most common among tier 1 and tier 2 targets.
    pub supports_stack_protector: bool,

    /// The name of entry function.
    /// Default value is "main"
    pub entry_name: StaticCow<str>,

    /// The ABI of entry function.
    /// Default value is `Conv::C`, i.e. C call convention
    pub entry_abi: Conv,

    /// Whether the target supports XRay instrumentation.
    pub supports_xray: bool,

    /// Forces the use of emulated TLS (__emutls_get_address)
    pub force_emulated_tls: bool,
}

/// Add arguments for the given flavor and also for its "twin" flavors
/// that have a compatible command line interface.
fn add_link_args_iter(
    link_args: &mut LinkArgs,
    flavor: LinkerFlavor,
    args: impl Iterator<Item = StaticCow<str>> + Clone,
) {
    let mut insert = |flavor| link_args.entry(flavor).or_default().extend(args.clone());
    insert(flavor);
    match flavor {
        LinkerFlavor::Gnu(cc, lld) => {
            assert_eq!(lld, Lld::No);
            insert(LinkerFlavor::Gnu(cc, Lld::Yes));
        }
        LinkerFlavor::Darwin(cc, lld) => {
            assert_eq!(lld, Lld::No);
            insert(LinkerFlavor::Darwin(cc, Lld::Yes));
        }
        LinkerFlavor::Msvc(lld) => {
            assert_eq!(lld, Lld::No);
            insert(LinkerFlavor::Msvc(Lld::Yes));
        }
        LinkerFlavor::WasmLld(..)
        | LinkerFlavor::Unix(..)
        | LinkerFlavor::EmCc
        | LinkerFlavor::Bpf
        | LinkerFlavor::Ptx => {}
    }
}

fn add_link_args(link_args: &mut LinkArgs, flavor: LinkerFlavor, args: &[&'static str]) {
    add_link_args_iter(link_args, flavor, args.iter().copied().map(Cow::Borrowed))
}

impl TargetOptions {
    fn link_args(flavor: LinkerFlavor, args: &[&'static str]) -> LinkArgs {
        let mut link_args = LinkArgs::new();
        add_link_args(&mut link_args, flavor, args);
        link_args
    }

    fn add_pre_link_args(&mut self, flavor: LinkerFlavor, args: &[&'static str]) {
        add_link_args(&mut self.pre_link_args, flavor, args);
    }

    fn add_post_link_args(&mut self, flavor: LinkerFlavor, args: &[&'static str]) {
        add_link_args(&mut self.post_link_args, flavor, args);
    }

    fn update_from_cli(&mut self) {
        self.linker_flavor = LinkerFlavor::from_cli_json(
            self.linker_flavor_json,
            self.lld_flavor_json,
            self.linker_is_gnu_json,
        );
        for (args, args_json) in [
            (&mut self.pre_link_args, &self.pre_link_args_json),
            (&mut self.late_link_args, &self.late_link_args_json),
            (&mut self.late_link_args_dynamic, &self.late_link_args_dynamic_json),
            (&mut self.late_link_args_static, &self.late_link_args_static_json),
            (&mut self.post_link_args, &self.post_link_args_json),
        ] {
            args.clear();
            for (flavor, args_json) in args_json {
                let linker_flavor = self.linker_flavor.with_cli_hints(*flavor);
                // Normalize to no lld to avoid asserts.
                let linker_flavor = match linker_flavor {
                    LinkerFlavor::Gnu(cc, _) => LinkerFlavor::Gnu(cc, Lld::No),
                    LinkerFlavor::Darwin(cc, _) => LinkerFlavor::Darwin(cc, Lld::No),
                    LinkerFlavor::Msvc(_) => LinkerFlavor::Msvc(Lld::No),
                    _ => linker_flavor,
                };
                if !args.contains_key(&linker_flavor) {
                    add_link_args_iter(args, linker_flavor, args_json.iter().cloned());
                }
            }
        }
    }

    fn update_to_cli(&mut self) {
        self.linker_flavor_json = self.linker_flavor.to_cli();
        self.lld_flavor_json = self.linker_flavor.lld_flavor();
        self.linker_is_gnu_json = self.linker_flavor.is_gnu();
        for (args, args_json) in [
            (&self.pre_link_args, &mut self.pre_link_args_json),
            (&self.late_link_args, &mut self.late_link_args_json),
            (&self.late_link_args_dynamic, &mut self.late_link_args_dynamic_json),
            (&self.late_link_args_static, &mut self.late_link_args_static_json),
            (&self.post_link_args, &mut self.post_link_args_json),
        ] {
            *args_json =
                args.iter().map(|(flavor, args)| (flavor.to_cli(), args.clone())).collect();
        }
    }
}

impl Default for TargetOptions {
    /// Creates a set of "sane defaults" for any target. This is still
    /// incomplete, and if used for compilation, will certainly not work.
    fn default() -> TargetOptions {
        TargetOptions {
            is_builtin: false,
            endian: Endian::Little,
            c_int_width: "32".into(),
            os: "none".into(),
            env: "".into(),
            abi: "".into(),
            vendor: "unknown".into(),
            linker: option_env!("CFG_DEFAULT_LINKER").map(|s| s.into()),
            linker_flavor: LinkerFlavor::Gnu(Cc::Yes, Lld::No),
            linker_flavor_json: LinkerFlavorCli::Gcc,
            lld_flavor_json: LldFlavor::Ld,
            linker_is_gnu_json: true,
            link_script: None,
            asm_args: cvs![],
            cpu: "generic".into(),
            features: "".into(),
            dynamic_linking: false,
            dll_tls_export: true,
            only_cdylib: false,
            executables: true,
            relocation_model: RelocModel::Pic,
            code_model: None,
            tls_model: TlsModel::GeneralDynamic,
            disable_redzone: false,
            frame_pointer: FramePointer::MayOmit,
            function_sections: true,
            dll_prefix: "lib".into(),
            dll_suffix: ".so".into(),
            exe_suffix: "".into(),
            staticlib_prefix: "lib".into(),
            staticlib_suffix: ".a".into(),
            families: cvs![],
            abi_return_struct_as_int: false,
            is_like_aix: false,
            is_like_osx: false,
            is_like_solaris: false,
            is_like_windows: false,
            is_like_msvc: false,
            is_like_wasm: false,
            is_like_android: false,
            default_dwarf_version: 4,
            allows_weak_linkage: true,
            has_rpath: false,
            no_default_libraries: true,
            position_independent_executables: false,
            static_position_independent_executables: false,
            plt_by_default: true,
            relro_level: RelroLevel::None,
            pre_link_objects: Default::default(),
            post_link_objects: Default::default(),
            pre_link_objects_self_contained: Default::default(),
            post_link_objects_self_contained: Default::default(),
            link_self_contained: LinkSelfContainedDefault::False,
            pre_link_args: LinkArgs::new(),
            pre_link_args_json: LinkArgsCli::new(),
            late_link_args: LinkArgs::new(),
            late_link_args_json: LinkArgsCli::new(),
            late_link_args_dynamic: LinkArgs::new(),
            late_link_args_dynamic_json: LinkArgsCli::new(),
            late_link_args_static: LinkArgs::new(),
            late_link_args_static_json: LinkArgsCli::new(),
            post_link_args: LinkArgs::new(),
            post_link_args_json: LinkArgsCli::new(),
            link_env: cvs![],
            link_env_remove: cvs![],
            archive_format: "gnu".into(),
            main_needs_argc_argv: true,
            allow_asm: true,
            has_thread_local: false,
            obj_is_bitcode: false,
            forces_embed_bitcode: false,
            bitcode_llvm_cmdline: "".into(),
            min_atomic_width: None,
            max_atomic_width: None,
            atomic_cas: true,
            panic_strategy: PanicStrategy::Unwind,
            crt_static_allows_dylibs: false,
            crt_static_default: false,
            crt_static_respected: false,
            stack_probes: StackProbeType::None,
            min_global_align: None,
            default_codegen_units: None,
            trap_unreachable: true,
            requires_lto: false,
            singlethread: false,
            no_builtins: false,
            default_hidden_visibility: false,
            emit_debug_gdb_scripts: true,
            requires_uwtable: false,
            default_uwtable: false,
            simd_types_indirect: true,
            limit_rdylib_exports: true,
            override_export_symbols: None,
            merge_functions: MergeFunctions::Aliases,
            mcount: "mcount".into(),
            llvm_mcount_intrinsic: None,
            llvm_abiname: "".into(),
            relax_elf_relocations: false,
            llvm_args: cvs![],
            use_ctors_section: false,
            eh_frame_header: true,
            has_thumb_interworking: false,
            debuginfo_kind: Default::default(),
            split_debuginfo: Default::default(),
            // `Off` is supported by default, but targets can remove this manually, e.g. Windows.
            supported_split_debuginfo: Cow::Borrowed(&[SplitDebuginfo::Off]),
            supported_sanitizers: SanitizerSet::empty(),
            default_adjusted_cabi: None,
            c_enum_min_bits: None,
            generate_arange_section: true,
            supports_stack_protector: true,
            entry_name: "main".into(),
            entry_abi: Conv::C,
            supports_xray: false,
            force_emulated_tls: false,
        }
    }
}

/// `TargetOptions` being a separate type is basically an implementation detail of `Target` that is
/// used for providing defaults. Perhaps there's a way to merge `TargetOptions` into `Target` so
/// this `Deref` implementation is no longer necessary.
impl Deref for Target {
    type Target = TargetOptions;

    #[inline]
    fn deref(&self) -> &Self::Target {
        &self.options
    }
}
impl DerefMut for Target {
    #[inline]
    fn deref_mut(&mut self) -> &mut Self::Target {
        &mut self.options
    }
}

impl Target {
    /// Given a function ABI, turn it into the correct ABI for this target.
    pub fn adjust_abi(&self, abi: Abi) -> Abi {
        match abi {
            Abi::C { .. } => self.default_adjusted_cabi.unwrap_or(abi),
            Abi::System { unwind } if self.is_like_windows && self.arch == "x86" => {
                Abi::Stdcall { unwind }
            }
            Abi::System { unwind } => Abi::C { unwind },
            Abi::EfiApi if self.arch == "arm" => Abi::Aapcs { unwind: false },
            Abi::EfiApi if self.arch == "x86_64" => Abi::Win64 { unwind: false },
            Abi::EfiApi => Abi::C { unwind: false },

            // See commentary in `is_abi_supported`.
            Abi::Stdcall { .. } | Abi::Thiscall { .. } if self.arch == "x86" => abi,
            Abi::Stdcall { unwind } | Abi::Thiscall { unwind } => Abi::C { unwind },
            Abi::Fastcall { .. } if self.arch == "x86" => abi,
            Abi::Vectorcall { .. } if ["x86", "x86_64"].contains(&&self.arch[..]) => abi,
            Abi::Fastcall { unwind } | Abi::Vectorcall { unwind } => Abi::C { unwind },

            // The Windows x64 calling convention we use for `extern "Rust"`
            // <https://learn.microsoft.com/en-us/cpp/build/x64-software-conventions#register-volatility-and-preservation>
            // expects the callee to save `xmm6` through `xmm15`, but `PreserveMost`
            // (that we use by default for `extern "rust-cold"`) doesn't save any of those.
            // So to avoid bloating callers, just use the Rust convention here.
            Abi::RustCold if self.is_like_windows && self.arch == "x86_64" => Abi::Rust,

            abi => abi,
        }
    }

    /// Returns a None if the UNSUPPORTED_CALLING_CONVENTIONS lint should be emitted
    pub fn is_abi_supported(&self, abi: Abi) -> Option<bool> {
        use Abi::*;
        Some(match abi {
            Rust
            | C { .. }
            | System { .. }
            | RustIntrinsic
            | RustCall
            | PlatformIntrinsic
            | Unadjusted
            | Cdecl { .. }
            | RustCold => true,
            EfiApi => {
                ["arm", "aarch64", "riscv32", "riscv64", "x86", "x86_64"].contains(&&self.arch[..])
            }
            X86Interrupt => ["x86", "x86_64"].contains(&&self.arch[..]),
            Aapcs { .. } => "arm" == self.arch,
            CCmseNonSecureCall => ["arm", "aarch64"].contains(&&self.arch[..]),
            Win64 { .. } | SysV64 { .. } => self.arch == "x86_64",
            PtxKernel => self.arch == "nvptx64",
            Msp430Interrupt => self.arch == "msp430",
            AmdGpuKernel => self.arch == "amdgcn",
            RiscvInterruptM | RiscvInterruptS => ["riscv32", "riscv64"].contains(&&self.arch[..]),
            AvrInterrupt | AvrNonBlockingInterrupt => self.arch == "avr",
            Wasm => ["wasm32", "wasm64"].contains(&&self.arch[..]),
            Thiscall { .. } => self.arch == "x86",
            // On windows these fall-back to platform native calling convention (C) when the
            // architecture is not supported.
            //
            // This is I believe a historical accident that has occurred as part of Microsoft
            // striving to allow most of the code to "just" compile when support for 64-bit x86
            // was added and then later again, when support for ARM architectures was added.
            //
            // This is well documented across MSDN. Support for this in Rust has been added in
            // #54576. This makes much more sense in context of Microsoft's C++ than it does in
            // Rust, but there isn't much leeway remaining here to change it back at the time this
            // comment has been written.
            //
            // Following are the relevant excerpts from the MSDN documentation.
            //
            // > The __vectorcall calling convention is only supported in native code on x86 and
            // x64 processors that include Streaming SIMD Extensions 2 (SSE2) and above.
            // > ...
            // > On ARM machines, __vectorcall is accepted and ignored by the compiler.
            //
            // -- https://docs.microsoft.com/en-us/cpp/cpp/vectorcall?view=msvc-160
            //
            // > On ARM and x64 processors, __stdcall is accepted and ignored by the compiler;
            //
            // -- https://docs.microsoft.com/en-us/cpp/cpp/stdcall?view=msvc-160
            //
            // > In most cases, keywords or compiler switches that specify an unsupported
            // > convention on a particular platform are ignored, and the platform default
            // > convention is used.
            //
            // -- https://docs.microsoft.com/en-us/cpp/cpp/argument-passing-and-naming-conventions
            Stdcall { .. } | Fastcall { .. } | Vectorcall { .. } if self.is_like_windows => true,
            // Outside of Windows we want to only support these calling conventions for the
            // architectures for which these calling conventions are actually well defined.
            Stdcall { .. } | Fastcall { .. } if self.arch == "x86" => true,
            Vectorcall { .. } if ["x86", "x86_64"].contains(&&self.arch[..]) => true,
            // Return a `None` for other cases so that we know to emit a future compat lint.
            Stdcall { .. } | Fastcall { .. } | Vectorcall { .. } => return None,
        })
    }

    /// Minimum integer size in bits that this target can perform atomic
    /// operations on.
    pub fn min_atomic_width(&self) -> u64 {
        self.min_atomic_width.unwrap_or(8)
    }

    /// Maximum integer size in bits that this target can perform atomic
    /// operations on.
    pub fn max_atomic_width(&self) -> u64 {
        self.max_atomic_width.unwrap_or_else(|| self.pointer_width.into())
    }

    /// Loads a target descriptor from a JSON object.
    pub fn from_json(obj: Json) -> Result<(Target, TargetWarnings), String> {
        // While ugly, this code must remain this way to retain
        // compatibility with existing JSON fields and the internal
        // expected naming of the Target and TargetOptions structs.
        // To ensure compatibility is retained, the built-in targets
        // are round-tripped through this code to catch cases where
        // the JSON parser is not updated to match the structs.

        let mut obj = match obj {
            Value::Object(obj) => obj,
            _ => return Err("Expected JSON object for target")?,
        };

        let mut get_req_field = |name: &str| {
            obj.remove(name)
                .and_then(|j| j.as_str().map(str::to_string))
                .ok_or_else(|| format!("Field {name} in target specification is required"))
        };

        let mut base = Target {
            llvm_target: get_req_field("llvm-target")?.into(),
            pointer_width: get_req_field("target-pointer-width")?
                .parse::<u32>()
                .map_err(|_| "target-pointer-width must be an integer".to_string())?,
            data_layout: get_req_field("data-layout")?.into(),
            arch: get_req_field("arch")?.into(),
            options: Default::default(),
        };

        let mut incorrect_type = vec![];

        macro_rules! key {
            ($key_name:ident) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                if let Some(s) = obj.remove(&name).and_then(|s| s.as_str().map(str::to_string).map(Cow::from)) {
                    base.$key_name = s;
                }
            } );
            ($key_name:ident = $json_name:expr) => ( {
                let name = $json_name;
                if let Some(s) = obj.remove(name).and_then(|s| s.as_str().map(str::to_string).map(Cow::from)) {
                    base.$key_name = s;
                }
            } );
            ($key_name:ident, bool) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                if let Some(s) = obj.remove(&name).and_then(|b| b.as_bool()) {
                    base.$key_name = s;
                }
            } );
            ($key_name:ident = $json_name:expr, bool) => ( {
                let name = $json_name;
                if let Some(s) = obj.remove(name).and_then(|b| b.as_bool()) {
                    base.$key_name = s;
                }
            } );
            ($key_name:ident, u32) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                if let Some(s) = obj.remove(&name).and_then(|b| b.as_u64()) {
                    if s < 1 || s > 5 {
                        return Err("Not a valid DWARF version number".into());
                    }
                    base.$key_name = s as u32;
                }
            } );
            ($key_name:ident, Option<u64>) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                if let Some(s) = obj.remove(&name).and_then(|b| b.as_u64()) {
                    base.$key_name = Some(s);
                }
            } );
            ($key_name:ident, MergeFunctions) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                obj.remove(&name).and_then(|o| o.as_str().and_then(|s| {
                    match s.parse::<MergeFunctions>() {
                        Ok(mergefunc) => base.$key_name = mergefunc,
                        _ => return Some(Err(format!("'{}' is not a valid value for \
                                                      merge-functions. Use 'disabled', \
                                                      'trampolines', or 'aliases'.",
                                                      s))),
                    }
                    Some(Ok(()))
                })).unwrap_or(Ok(()))
            } );
            ($key_name:ident, RelocModel) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                obj.remove(&name).and_then(|o| o.as_str().and_then(|s| {
                    match s.parse::<RelocModel>() {
                        Ok(relocation_model) => base.$key_name = relocation_model,
                        _ => return Some(Err(format!("'{}' is not a valid relocation model. \
                                                      Run `rustc --print relocation-models` to \
                                                      see the list of supported values.", s))),
                    }
                    Some(Ok(()))
                })).unwrap_or(Ok(()))
            } );
            ($key_name:ident, CodeModel) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                obj.remove(&name).and_then(|o| o.as_str().and_then(|s| {
                    match s.parse::<CodeModel>() {
                        Ok(code_model) => base.$key_name = Some(code_model),
                        _ => return Some(Err(format!("'{}' is not a valid code model. \
                                                      Run `rustc --print code-models` to \
                                                      see the list of supported values.", s))),
                    }
                    Some(Ok(()))
                })).unwrap_or(Ok(()))
            } );
            ($key_name:ident, TlsModel) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                obj.remove(&name).and_then(|o| o.as_str().and_then(|s| {
                    match s.parse::<TlsModel>() {
                        Ok(tls_model) => base.$key_name = tls_model,
                        _ => return Some(Err(format!("'{}' is not a valid TLS model. \
                                                      Run `rustc --print tls-models` to \
                                                      see the list of supported values.", s))),
                    }
                    Some(Ok(()))
                })).unwrap_or(Ok(()))
            } );
            ($key_name:ident, PanicStrategy) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                obj.remove(&name).and_then(|o| o.as_str().and_then(|s| {
                    match s {
                        "unwind" => base.$key_name = PanicStrategy::Unwind,
                        "abort" => base.$key_name = PanicStrategy::Abort,
                        _ => return Some(Err(format!("'{}' is not a valid value for \
                                                      panic-strategy. Use 'unwind' or 'abort'.",
                                                     s))),
                }
                Some(Ok(()))
            })).unwrap_or(Ok(()))
            } );
            ($key_name:ident, RelroLevel) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                obj.remove(&name).and_then(|o| o.as_str().and_then(|s| {
                    match s.parse::<RelroLevel>() {
                        Ok(level) => base.$key_name = level,
                        _ => return Some(Err(format!("'{}' is not a valid value for \
                                                      relro-level. Use 'full', 'partial, or 'off'.",
                                                      s))),
                    }
                    Some(Ok(()))
                })).unwrap_or(Ok(()))
            } );
            ($key_name:ident, DebuginfoKind) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                obj.remove(&name).and_then(|o| o.as_str().and_then(|s| {
                    match s.parse::<DebuginfoKind>() {
                        Ok(level) => base.$key_name = level,
                        _ => return Some(Err(
                            format!("'{s}' is not a valid value for debuginfo-kind. Use 'dwarf', \
                                  'dwarf-dsym' or 'pdb'.")
                        )),
                    }
                    Some(Ok(()))
                })).unwrap_or(Ok(()))
            } );
            ($key_name:ident, SplitDebuginfo) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                obj.remove(&name).and_then(|o| o.as_str().and_then(|s| {
                    match s.parse::<SplitDebuginfo>() {
                        Ok(level) => base.$key_name = level,
                        _ => return Some(Err(format!("'{}' is not a valid value for \
                                                      split-debuginfo. Use 'off' or 'dsymutil'.",
                                                      s))),
                    }
                    Some(Ok(()))
                })).unwrap_or(Ok(()))
            } );
            ($key_name:ident, list) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                if let Some(j) = obj.remove(&name) {
                    if let Some(v) = j.as_array() {
                        base.$key_name = v.iter()
                            .map(|a| a.as_str().unwrap().to_string().into())
                            .collect();
                    } else {
                        incorrect_type.push(name)
                    }
                }
            } );
            ($key_name:ident, opt_list) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                if let Some(j) = obj.remove(&name) {
                    if let Some(v) = j.as_array() {
                        base.$key_name = Some(v.iter()
                            .map(|a| a.as_str().unwrap().to_string().into())
                            .collect());
                    } else {
                        incorrect_type.push(name)
                    }
                }
            } );
            ($key_name:ident, fallible_list) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                obj.remove(&name).and_then(|j| {
                    if let Some(v) = j.as_array() {
                        match v.iter().map(|a| FromStr::from_str(a.as_str().unwrap())).collect() {
                            Ok(l) => { base.$key_name = l },
                            // FIXME: `fallible_list` can't re-use the `key!` macro for list
                            // elements and the error messages from that macro, so it has a bad
                            // generic message instead
                            Err(_) => return Some(Err(
                                format!("`{:?}` is not a valid value for `{}`", j, name)
                            )),
                        }
                    } else {
                        incorrect_type.push(name)
                    }
                    Some(Ok(()))
                }).unwrap_or(Ok(()))
            } );
            ($key_name:ident, optional) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                if let Some(o) = obj.remove(&name) {
                    base.$key_name = o
                        .as_str()
                        .map(|s| s.to_string().into());
                }
            } );
            ($key_name:ident = $json_name:expr, LldFlavor) => ( {
                let name = $json_name;
                obj.remove(name).and_then(|o| o.as_str().and_then(|s| {
                    if let Some(flavor) = LldFlavor::from_str(&s) {
                        base.$key_name = flavor;
                    } else {
                        return Some(Err(format!(
                            "'{}' is not a valid value for lld-flavor. \
                             Use 'darwin', 'gnu', 'link' or 'wasm'.",
                            s)))
                    }
                    Some(Ok(()))
                })).unwrap_or(Ok(()))
            } );
            ($key_name:ident = $json_name:expr, LinkerFlavor) => ( {
                let name = $json_name;
                obj.remove(name).and_then(|o| o.as_str().and_then(|s| {
                    match LinkerFlavorCli::from_str(s) {
                        Some(linker_flavor) => base.$key_name = linker_flavor,
                        _ => return Some(Err(format!("'{}' is not a valid value for linker-flavor. \
                                                      Use {}", s, LinkerFlavorCli::one_of()))),
                    }
                    Some(Ok(()))
                })).unwrap_or(Ok(()))
            } );
            ($key_name:ident, StackProbeType) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                obj.remove(&name).and_then(|o| match StackProbeType::from_json(&o) {
                    Ok(v) => {
                        base.$key_name = v;
                        Some(Ok(()))
                    },
                    Err(s) => Some(Err(
                        format!("`{:?}` is not a valid value for `{}`: {}", o, name, s)
                    )),
                }).unwrap_or(Ok(()))
            } );
            ($key_name:ident, SanitizerSet) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                if let Some(o) = obj.remove(&name) {
                    if let Some(a) = o.as_array() {
                        for s in a {
                            base.$key_name |= match s.as_str() {
                                Some("address") => SanitizerSet::ADDRESS,
                                Some("cfi") => SanitizerSet::CFI,
                                Some("kcfi") => SanitizerSet::KCFI,
                                Some("kernel-address") => SanitizerSet::KERNELADDRESS,
                                Some("leak") => SanitizerSet::LEAK,
                                Some("memory") => SanitizerSet::MEMORY,
                                Some("memtag") => SanitizerSet::MEMTAG,
                                Some("safestack") => SanitizerSet::SAFESTACK,
                                Some("shadow-call-stack") => SanitizerSet::SHADOWCALLSTACK,
                                Some("thread") => SanitizerSet::THREAD,
                                Some("hwaddress") => SanitizerSet::HWADDRESS,
                                Some(s) => return Err(format!("unknown sanitizer {}", s)),
                                _ => return Err(format!("not a string: {:?}", s)),
                            };
                        }
                    } else {
                        incorrect_type.push(name)
                    }
                }
                Ok::<(), String>(())
            } );

            ($key_name:ident = $json_name:expr, link_self_contained) => ( {
                let name = $json_name;
                obj.remove(name).and_then(|o| o.as_str().and_then(|s| {
                    match s.parse::<LinkSelfContainedDefault>() {
                        Ok(lsc_default) => base.$key_name = lsc_default,
                        _ => return Some(Err(format!("'{}' is not a valid `-Clink-self-contained` default. \
                                                      Use 'false', 'true', 'musl' or 'mingw'", s))),
                    }
                    Some(Ok(()))
                })).unwrap_or(Ok(()))
            } );
            ($key_name:ident = $json_name:expr, link_objects) => ( {
                let name = $json_name;
                if let Some(val) = obj.remove(name) {
                    let obj = val.as_object().ok_or_else(|| format!("{}: expected a \
                        JSON object with fields per CRT object kind.", name))?;
                    let mut args = CrtObjects::new();
                    for (k, v) in obj {
                        let kind = LinkOutputKind::from_str(&k).ok_or_else(|| {
                            format!("{}: '{}' is not a valid value for CRT object kind. \
                                     Use '(dynamic,static)-(nopic,pic)-exe' or \
                                     '(dynamic,static)-dylib' or 'wasi-reactor-exe'", name, k)
                        })?;

                        let v = v.as_array().ok_or_else(||
                            format!("{}.{}: expected a JSON array", name, k)
                        )?.iter().enumerate()
                            .map(|(i,s)| {
                                let s = s.as_str().ok_or_else(||
                                    format!("{}.{}[{}]: expected a JSON string", name, k, i))?;
                                Ok(s.to_string().into())
                            })
                            .collect::<Result<Vec<_>, String>>()?;

                        args.insert(kind, v);
                    }
                    base.$key_name = args;
                }
            } );
            ($key_name:ident = $json_name:expr, link_args) => ( {
                let name = $json_name;
                if let Some(val) = obj.remove(name) {
                    let obj = val.as_object().ok_or_else(|| format!("{}: expected a \
                        JSON object with fields per linker-flavor.", name))?;
                    let mut args = LinkArgsCli::new();
                    for (k, v) in obj {
                        let flavor = LinkerFlavorCli::from_str(&k).ok_or_else(|| {
                            format!("{}: '{}' is not a valid value for linker-flavor. \
                                     Use 'em', 'gcc', 'ld' or 'msvc'", name, k)
                        })?;

                        let v = v.as_array().ok_or_else(||
                            format!("{}.{}: expected a JSON array", name, k)
                        )?.iter().enumerate()
                            .map(|(i,s)| {
                                let s = s.as_str().ok_or_else(||
                                    format!("{}.{}[{}]: expected a JSON string", name, k, i))?;
                                Ok(s.to_string().into())
                            })
                            .collect::<Result<Vec<_>, String>>()?;

                        args.insert(flavor, v);
                    }
                    base.$key_name = args;
                }
            } );
            ($key_name:ident, env) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                if let Some(o) = obj.remove(&name) {
                    if let Some(a) = o.as_array() {
                        for o in a {
                            if let Some(s) = o.as_str() {
                                let p = s.split('=').collect::<Vec<_>>();
                                if p.len() == 2 {
                                    let k = p[0].to_string();
                                    let v = p[1].to_string();
                                    base.$key_name.to_mut().push((k.into(), v.into()));
                                }
                            }
                        }
                    } else {
                        incorrect_type.push(name)
                    }
                }
            } );
            ($key_name:ident, Option<Abi>) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                obj.remove(&name).and_then(|o| o.as_str().and_then(|s| {
                    match lookup_abi(s) {
                        Ok(abi) => base.$key_name = Some(abi),
                        _ => return Some(Err(format!("'{}' is not a valid value for abi", s))),
                    }
                    Some(Ok(()))
                })).unwrap_or(Ok(()))
            } );
            ($key_name:ident, TargetFamilies) => ( {
                if let Some(value) = obj.remove("target-family") {
                    if let Some(v) = value.as_array() {
                        base.$key_name = v.iter()
                            .map(|a| a.as_str().unwrap().to_string().into())
                            .collect();
                    } else if let Some(v) = value.as_str() {
                        base.$key_name = vec![v.to_string().into()].into();
                    }
                }
            } );
            ($key_name:ident, Conv) => ( {
                let name = (stringify!($key_name)).replace("_", "-");
                obj.remove(&name).and_then(|o| o.as_str().and_then(|s| {
                    match Conv::from_str(s) {
                        Ok(c) => {
                            base.$key_name = c;
                            Some(Ok(()))
                        }
                        Err(e) => Some(Err(e))
                    }
                })).unwrap_or(Ok(()))
            } );
        }

        if let Some(j) = obj.remove("target-endian") {
            if let Some(s) = j.as_str() {
                base.endian = s.parse()?;
            } else {
                incorrect_type.push("target-endian".into())
            }
        }

        if let Some(fp) = obj.remove("frame-pointer") {
            if let Some(s) = fp.as_str() {
                base.frame_pointer = s
                    .parse()
                    .map_err(|()| format!("'{s}' is not a valid value for frame-pointer"))?;
            } else {
                incorrect_type.push("frame-pointer".into())
            }
        }

        key!(is_builtin, bool);
        key!(c_int_width = "target-c-int-width");
        key!(c_enum_min_bits, Option<u64>); // if None, matches c_int_width
        key!(os);
        key!(env);
        key!(abi);
        key!(vendor);
        key!(linker, optional);
        key!(linker_flavor_json = "linker-flavor", LinkerFlavor)?;
        key!(lld_flavor_json = "lld-flavor", LldFlavor)?;
        key!(linker_is_gnu_json = "linker-is-gnu", bool);
        key!(pre_link_objects = "pre-link-objects", link_objects);
        key!(post_link_objects = "post-link-objects", link_objects);
        key!(pre_link_objects_self_contained = "pre-link-objects-fallback", link_objects);
        key!(post_link_objects_self_contained = "post-link-objects-fallback", link_objects);
        key!(link_self_contained = "crt-objects-fallback", link_self_contained)?;
        key!(pre_link_args_json = "pre-link-args", link_args);
        key!(late_link_args_json = "late-link-args", link_args);
        key!(late_link_args_dynamic_json = "late-link-args-dynamic", link_args);
        key!(late_link_args_static_json = "late-link-args-static", link_args);
        key!(post_link_args_json = "post-link-args", link_args);
        key!(link_script, optional);
        key!(link_env, env);
        key!(link_env_remove, list);
        key!(asm_args, list);
        key!(cpu);
        key!(features);
        key!(dynamic_linking, bool);
        key!(dll_tls_export, bool);
        key!(only_cdylib, bool);
        key!(executables, bool);
        key!(relocation_model, RelocModel)?;
        key!(code_model, CodeModel)?;
        key!(tls_model, TlsModel)?;
        key!(disable_redzone, bool);
        key!(function_sections, bool);
        key!(dll_prefix);
        key!(dll_suffix);
        key!(exe_suffix);
        key!(staticlib_prefix);
        key!(staticlib_suffix);
        key!(families, TargetFamilies);
        key!(abi_return_struct_as_int, bool);
        key!(is_like_aix, bool);
        key!(is_like_osx, bool);
        key!(is_like_solaris, bool);
        key!(is_like_windows, bool);
        key!(is_like_msvc, bool);
        key!(is_like_wasm, bool);
        key!(is_like_android, bool);
        key!(default_dwarf_version, u32);
        key!(allows_weak_linkage, bool);
        key!(has_rpath, bool);
        key!(no_default_libraries, bool);
        key!(position_independent_executables, bool);
        key!(static_position_independent_executables, bool);
        key!(plt_by_default, bool);
        key!(relro_level, RelroLevel)?;
        key!(archive_format);
        key!(allow_asm, bool);
        key!(main_needs_argc_argv, bool);
        key!(has_thread_local, bool);
        key!(obj_is_bitcode, bool);
        key!(forces_embed_bitcode, bool);
        key!(bitcode_llvm_cmdline);
        key!(max_atomic_width, Option<u64>);
        key!(min_atomic_width, Option<u64>);
        key!(atomic_cas, bool);
        key!(panic_strategy, PanicStrategy)?;
        key!(crt_static_allows_dylibs, bool);
        key!(crt_static_default, bool);
        key!(crt_static_respected, bool);
        key!(stack_probes, StackProbeType)?;
        key!(min_global_align, Option<u64>);
        key!(default_codegen_units, Option<u64>);
        key!(trap_unreachable, bool);
        key!(requires_lto, bool);
        key!(singlethread, bool);
        key!(no_builtins, bool);
        key!(default_hidden_visibility, bool);
        key!(emit_debug_gdb_scripts, bool);
        key!(requires_uwtable, bool);
        key!(default_uwtable, bool);
        key!(simd_types_indirect, bool);
        key!(limit_rdylib_exports, bool);
        key!(override_export_symbols, opt_list);
        key!(merge_functions, MergeFunctions)?;
        key!(mcount = "target-mcount");
        key!(llvm_mcount_intrinsic, optional);
        key!(llvm_abiname);
        key!(relax_elf_relocations, bool);
        key!(llvm_args, list);
        key!(use_ctors_section, bool);
        key!(eh_frame_header, bool);
        key!(has_thumb_interworking, bool);
        key!(debuginfo_kind, DebuginfoKind)?;
        key!(split_debuginfo, SplitDebuginfo)?;
        key!(supported_split_debuginfo, fallible_list)?;
        key!(supported_sanitizers, SanitizerSet)?;
        key!(default_adjusted_cabi, Option<Abi>)?;
        key!(generate_arange_section, bool);
        key!(supports_stack_protector, bool);
        key!(entry_name);
        key!(entry_abi, Conv)?;
        key!(supports_xray, bool);
        key!(force_emulated_tls, bool);

        if base.is_builtin {
            // This can cause unfortunate ICEs later down the line.
            return Err("may not set is_builtin for targets not built-in".into());
        }
        base.update_from_cli();

        // Each field should have been read using `Json::remove` so any keys remaining are unused.
        let remaining_keys = obj.keys();
        Ok((
            base,
            TargetWarnings { unused_fields: remaining_keys.cloned().collect(), incorrect_type },
        ))
    }

    /// Load a built-in target
    pub fn expect_builtin(target_triple: &TargetTriple) -> Target {
        match *target_triple {
            TargetTriple::TargetTriple(ref target_triple) => {
                load_builtin(target_triple).expect("built-in target")
            }
            TargetTriple::TargetJson { .. } => {
                panic!("built-in targets doesn't support target-paths")
            }
        }
    }

    /// Search for a JSON file specifying the given target triple.
    ///
    /// If none is found in `$RUST_TARGET_PATH`, look for a file called `target.json` inside the
    /// sysroot under the target-triple's `rustlib` directory. Note that it could also just be a
    /// bare filename already, so also check for that. If one of the hardcoded targets we know
    /// about, just return it directly.
    ///
    /// The error string could come from any of the APIs called, including filesystem access and
    /// JSON decoding.
    pub fn search(
        target_triple: &TargetTriple,
        sysroot: &Path,
    ) -> Result<(Target, TargetWarnings), String> {
        use std::env;
        use std::fs;

        fn load_file(path: &Path) -> Result<(Target, TargetWarnings), String> {
            let contents = fs::read_to_string(path).map_err(|e| e.to_string())?;
            let obj = serde_json::from_str(&contents).map_err(|e| e.to_string())?;
            Target::from_json(obj)
        }

        match *target_triple {
            TargetTriple::TargetTriple(ref target_triple) => {
                // check if triple is in list of built-in targets
                if let Some(t) = load_builtin(target_triple) {
                    return Ok((t, TargetWarnings::empty()));
                }

                // search for a file named `target_triple`.json in RUST_TARGET_PATH
                let path = {
                    let mut target = target_triple.to_string();
                    target.push_str(".json");
                    PathBuf::from(target)
                };

                let target_path = env::var_os("RUST_TARGET_PATH").unwrap_or_default();

                for dir in env::split_paths(&target_path) {
                    let p = dir.join(&path);
                    if p.is_file() {
                        return load_file(&p);
                    }
                }

                // Additionally look in the sysroot under `lib/rustlib/<triple>/target.json`
                // as a fallback.
                let rustlib_path = crate::target_rustlib_path(sysroot, target_triple);
                let p = PathBuf::from_iter([
                    Path::new(sysroot),
                    Path::new(&rustlib_path),
                    Path::new("target.json"),
                ]);
                if p.is_file() {
                    return load_file(&p);
                }

                Err(format!("Could not find specification for target {target_triple:?}"))
            }
            TargetTriple::TargetJson { ref contents, .. } => {
                let obj = serde_json::from_str(contents).map_err(|e| e.to_string())?;
                Target::from_json(obj)
            }
        }
    }
}

impl ToJson for Target {
    fn to_json(&self) -> Json {
        let mut d = serde_json::Map::new();
        let default: TargetOptions = Default::default();
        let mut target = self.clone();
        target.update_to_cli();

        macro_rules! target_val {
            ($attr:ident) => {{
                let name = (stringify!($attr)).replace("_", "-");
                d.insert(name, target.$attr.to_json());
            }};
        }

        macro_rules! target_option_val {
            ($attr:ident) => {{
                let name = (stringify!($attr)).replace("_", "-");
                if default.$attr != target.$attr {
                    d.insert(name, target.$attr.to_json());
                }
            }};
            ($attr:ident, $json_name:expr) => {{
                let name = $json_name;
                if default.$attr != target.$attr {
                    d.insert(name.into(), target.$attr.to_json());
                }
            }};
            (link_args - $attr:ident, $json_name:expr) => {{
                let name = $json_name;
                if default.$attr != target.$attr {
                    let obj = target
                        .$attr
                        .iter()
                        .map(|(k, v)| (k.desc().to_string(), v.clone()))
                        .collect::<BTreeMap<_, _>>();
                    d.insert(name.to_string(), obj.to_json());
                }
            }};
            (env - $attr:ident) => {{
                let name = (stringify!($attr)).replace("_", "-");
                if default.$attr != target.$attr {
                    let obj = target
                        .$attr
                        .iter()
                        .map(|&(ref k, ref v)| format!("{k}={v}"))
                        .collect::<Vec<_>>();
                    d.insert(name, obj.to_json());
                }
            }};
        }

        target_val!(llvm_target);
        d.insert("target-pointer-width".to_string(), self.pointer_width.to_string().to_json());
        target_val!(arch);
        target_val!(data_layout);

        target_option_val!(is_builtin);
        target_option_val!(endian, "target-endian");
        target_option_val!(c_int_width, "target-c-int-width");
        target_option_val!(os);
        target_option_val!(env);
        target_option_val!(abi);
        target_option_val!(vendor);
        target_option_val!(linker);
        target_option_val!(linker_flavor_json, "linker-flavor");
        target_option_val!(lld_flavor_json, "lld-flavor");
        target_option_val!(linker_is_gnu_json, "linker-is-gnu");
        target_option_val!(pre_link_objects);
        target_option_val!(post_link_objects);
        target_option_val!(pre_link_objects_self_contained, "pre-link-objects-fallback");
        target_option_val!(post_link_objects_self_contained, "post-link-objects-fallback");
        target_option_val!(link_self_contained, "crt-objects-fallback");
        target_option_val!(link_args - pre_link_args_json, "pre-link-args");
        target_option_val!(link_args - late_link_args_json, "late-link-args");
        target_option_val!(link_args - late_link_args_dynamic_json, "late-link-args-dynamic");
        target_option_val!(link_args - late_link_args_static_json, "late-link-args-static");
        target_option_val!(link_args - post_link_args_json, "post-link-args");
        target_option_val!(link_script);
        target_option_val!(env - link_env);
        target_option_val!(link_env_remove);
        target_option_val!(asm_args);
        target_option_val!(cpu);
        target_option_val!(features);
        target_option_val!(dynamic_linking);
        target_option_val!(dll_tls_export);
        target_option_val!(only_cdylib);
        target_option_val!(executables);
        target_option_val!(relocation_model);
        target_option_val!(code_model);
        target_option_val!(tls_model);
        target_option_val!(disable_redzone);
        target_option_val!(frame_pointer);
        target_option_val!(function_sections);
        target_option_val!(dll_prefix);
        target_option_val!(dll_suffix);
        target_option_val!(exe_suffix);
        target_option_val!(staticlib_prefix);
        target_option_val!(staticlib_suffix);
        target_option_val!(families, "target-family");
        target_option_val!(abi_return_struct_as_int);
        target_option_val!(is_like_aix);
        target_option_val!(is_like_osx);
        target_option_val!(is_like_solaris);
        target_option_val!(is_like_windows);
        target_option_val!(is_like_msvc);
        target_option_val!(is_like_wasm);
        target_option_val!(is_like_android);
        target_option_val!(default_dwarf_version);
        target_option_val!(allows_weak_linkage);
        target_option_val!(has_rpath);
        target_option_val!(no_default_libraries);
        target_option_val!(position_independent_executables);
        target_option_val!(static_position_independent_executables);
        target_option_val!(plt_by_default);
        target_option_val!(relro_level);
        target_option_val!(archive_format);
        target_option_val!(allow_asm);
        target_option_val!(main_needs_argc_argv);
        target_option_val!(has_thread_local);
        target_option_val!(obj_is_bitcode);
        target_option_val!(forces_embed_bitcode);
        target_option_val!(bitcode_llvm_cmdline);
        target_option_val!(min_atomic_width);
        target_option_val!(max_atomic_width);
        target_option_val!(atomic_cas);
        target_option_val!(panic_strategy);
        target_option_val!(crt_static_allows_dylibs);
        target_option_val!(crt_static_default);
        target_option_val!(crt_static_respected);
        target_option_val!(stack_probes);
        target_option_val!(min_global_align);
        target_option_val!(default_codegen_units);
        target_option_val!(trap_unreachable);
        target_option_val!(requires_lto);
        target_option_val!(singlethread);
        target_option_val!(no_builtins);
        target_option_val!(default_hidden_visibility);
        target_option_val!(emit_debug_gdb_scripts);
        target_option_val!(requires_uwtable);
        target_option_val!(default_uwtable);
        target_option_val!(simd_types_indirect);
        target_option_val!(limit_rdylib_exports);
        target_option_val!(override_export_symbols);
        target_option_val!(merge_functions);
        target_option_val!(mcount, "target-mcount");
        target_option_val!(llvm_mcount_intrinsic);
        target_option_val!(llvm_abiname);
        target_option_val!(relax_elf_relocations);
        target_option_val!(llvm_args);
        target_option_val!(use_ctors_section);
        target_option_val!(eh_frame_header);
        target_option_val!(has_thumb_interworking);
        target_option_val!(debuginfo_kind);
        target_option_val!(split_debuginfo);
        target_option_val!(supported_split_debuginfo);
        target_option_val!(supported_sanitizers);
        target_option_val!(c_enum_min_bits);
        target_option_val!(generate_arange_section);
        target_option_val!(supports_stack_protector);
        target_option_val!(entry_name);
        target_option_val!(entry_abi);
        target_option_val!(supports_xray);
        target_option_val!(force_emulated_tls);

        if let Some(abi) = self.default_adjusted_cabi {
            d.insert("default-adjusted-cabi".into(), Abi::name(abi).to_json());
        }

        Json::Object(d)
    }
}

/// Either a target triple string or a path to a JSON file.
#[derive(Clone, Debug)]
pub enum TargetTriple {
    TargetTriple(String),
    TargetJson {
        /// Warning: This field may only be used by rustdoc. Using it anywhere else will lead to
        /// inconsistencies as it is discarded during serialization.
        path_for_rustdoc: PathBuf,
        triple: String,
        contents: String,
    },
}

// Use a manual implementation to ignore the path field
impl PartialEq for TargetTriple {
    fn eq(&self, other: &Self) -> bool {
        match (self, other) {
            (Self::TargetTriple(l0), Self::TargetTriple(r0)) => l0 == r0,
            (
                Self::TargetJson { path_for_rustdoc: _, triple: l_triple, contents: l_contents },
                Self::TargetJson { path_for_rustdoc: _, triple: r_triple, contents: r_contents },
            ) => l_triple == r_triple && l_contents == r_contents,
            _ => false,
        }
    }
}

// Use a manual implementation to ignore the path field
impl Hash for TargetTriple {
    fn hash<H: Hasher>(&self, state: &mut H) -> () {
        match self {
            TargetTriple::TargetTriple(triple) => {
                0u8.hash(state);
                triple.hash(state)
            }
            TargetTriple::TargetJson { path_for_rustdoc: _, triple, contents } => {
                1u8.hash(state);
                triple.hash(state);
                contents.hash(state)
            }
        }
    }
}

// Use a manual implementation to prevent encoding the target json file path in the crate metadata
impl<S: Encoder> Encodable<S> for TargetTriple {
    fn encode(&self, s: &mut S) {
        match self {
            TargetTriple::TargetTriple(triple) => s.emit_enum_variant(0, |s| s.emit_str(triple)),
            TargetTriple::TargetJson { path_for_rustdoc: _, triple, contents } => s
                .emit_enum_variant(1, |s| {
                    s.emit_str(triple);
                    s.emit_str(contents)
                }),
        }
    }
}

impl<D: Decoder> Decodable<D> for TargetTriple {
    fn decode(d: &mut D) -> Self {
        match d.read_usize() {
            0 => TargetTriple::TargetTriple(d.read_str().to_owned()),
            1 => TargetTriple::TargetJson {
                path_for_rustdoc: PathBuf::new(),
                triple: d.read_str().to_owned(),
                contents: d.read_str().to_owned(),
            },
            _ => {
                panic!("invalid enum variant tag while decoding `TargetTriple`, expected 0..2");
            }
        }
    }
}

impl TargetTriple {
    /// Creates a target triple from the passed target triple string.
    pub fn from_triple(triple: &str) -> Self {
        TargetTriple::TargetTriple(triple.into())
    }

    /// Creates a target triple from the passed target path.
    pub fn from_path(path: &Path) -> Result<Self, io::Error> {
        let canonicalized_path = try_canonicalize(path)?;
        let contents = std::fs::read_to_string(&canonicalized_path).map_err(|err| {
            io::Error::new(
                io::ErrorKind::InvalidInput,
                format!("target path {canonicalized_path:?} is not a valid file: {err}"),
            )
        })?;
        let triple = canonicalized_path
            .file_stem()
            .expect("target path must not be empty")
            .to_str()
            .expect("target path must be valid unicode")
            .to_owned();
        Ok(TargetTriple::TargetJson { path_for_rustdoc: canonicalized_path, triple, contents })
    }

    /// Returns a string triple for this target.
    ///
    /// If this target is a path, the file name (without extension) is returned.
    pub fn triple(&self) -> &str {
        match *self {
            TargetTriple::TargetTriple(ref triple)
            | TargetTriple::TargetJson { ref triple, .. } => triple,
        }
    }

    /// Returns an extended string triple for this target.
    ///
    /// If this target is a path, a hash of the path is appended to the triple returned
    /// by `triple()`.
    pub fn debug_triple(&self) -> String {
        use std::collections::hash_map::DefaultHasher;

        match self {
            TargetTriple::TargetTriple(triple) => triple.to_owned(),
            TargetTriple::TargetJson { path_for_rustdoc: _, triple, contents: content } => {
                let mut hasher = DefaultHasher::new();
                content.hash(&mut hasher);
                let hash = hasher.finish();
                format!("{triple}-{hash}")
            }
        }
    }
}

impl fmt::Display for TargetTriple {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        write!(f, "{}", self.debug_triple())
    }
}