Piotr Caban (@piotr) commented about dlls/msvcp140/tests/msvcp140.c:
+{ + int i; + FILE *f; + char *oldloc; + static const struct { + const char *loc; + const WCHAR *wpath; + const char *apath; + int is_todo; + } tests[] = { + { "C", L"utf_\x00e4\x00cf\x00f6\x00df.txt", "utf_\xe4\xcf\xf6\xdf.txt" }, + { "de_DE", L"utf_\x00e4\x00cf\x00f6\x00df.txt", "utf_\xe4\xcf\xf6\xdf.txt" }, + { "de_DE.utf8", L"utf_\x00e4\x00cf\x00f6\x00df.txt", "utf_\xc3\xa4\xc3\x8f\xc3\xb6\xc3\x9f.txt", TRUE }, + }; + + oldloc = p_setlocale(LC_ALL, NULL); You can't store setlocale return like this - it's get invalidated when locale is changed. Please restore to C locale instead.
-- https://gitlab.winehq.org/wine/wine/-/merge_requests/6680#note_85477