Fix lc_collate_is_c() when LC_COLLATE != LC_CTYPE.

jeff-davis · jeff-davis · commit 8148e7124d55 · 2024-11-06T14:44:35.000-08:00
An unfortunate typo in commit 2d819a0 can cause wrong results when the default collation provider is libc, LC_CTYPE=C, and LC_COLLATE is a real locale. Users with this combination of settings must REINDEX all affected indexes. The same typo can also cause performance degradation when LC_COLLATE=C and LC_CTYPE is a real locale. Problem does not exist in master (due to refactoring), so fix only in version 17. Reported-by: Drew Callahan Discussion: https://postgr.es/m/d5081a7f4f6d425c28dd69d1e09b2e78f149e726.camel@j-davis.com
diff --git a/src/backend/utils/adt/pg_locale.c b/src/backend/utils/adt/pg_locale.c
@@ -1370,9 +1370,9 @@ lc_collate_is_c(Oid collation)
 		}
 		else if (default_locale.provider == COLLPROVIDER_LIBC)
 		{
-			localeptr = setlocale(LC_CTYPE, NULL);
+			localeptr = setlocale(LC_COLLATE, NULL);
 			if (!localeptr)
-				elog(ERROR, "invalid LC_CTYPE setting");
+				elog(ERROR, "invalid LC_COLLATE setting");
 		}
 		else
 			elog(ERROR, "unexpected collation provider '%c'",

Original file line number	Diff line number	Diff line change
`@@ -1370,9 +1370,9 @@ lc_collate_is_c(Oid collation)`
`1370`	`1370`	`}`
`1371`	`1371`	`else if (default_locale.provider == COLLPROVIDER_LIBC)`
`1372`	`1372`	`{`
`1373`		`- localeptr = setlocale(LC_CTYPE, NULL);`
	`1373`	`+ localeptr = setlocale(LC_COLLATE, NULL);`
`1374`	`1374`	`if (!localeptr)`
`1375`		`- elog(ERROR, "invalid LC_CTYPE setting");`
	`1375`	`+ elog(ERROR, "invalid LC_COLLATE setting");`
`1376`	`1376`	`}`
`1377`	`1377`	`else`
`1378`	`1378`	`elog(ERROR, "unexpected collation provider '%c'",`