cc -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations stdlib/qsort_r.c -o stdlib/qsort_r -D_POSIX_C_SOURCE=202405L  -lm -lpthread  -liconv
stdlib/qsort_r.c:5:92: error: use of undeclared identifier 'qsort_r'; did you mean 'qsort'?
    5 | void (*foo)(void *, size_t, size_t, int (*)(const void *, const void *, void *), void *) = qsort_r;
      |                                                                                            ^~~~~~~
      |                                                                                            qsort
/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include/_stdlib.h:156:7: note: 'qsort' declared here
  156 | void     qsort(void *__base, size_t __nel, size_t __width,
      |          ^
stdlib/qsort_r.c:5:8: error: incompatible function pointer types initializing 'void (*)(void *, size_t, size_t, int (*)(const void *, const void *, void *), void *)' (aka 'void (*)(void *, unsigned long, unsigned long, int (*)(const void *, const void *, void *), void *)') with an expression of type 'void (void *, size_t, size_t, int (* _Nonnull)(const void *, const void *))' (aka 'void (void *, unsigned long, unsigned long, int (* _Nonnull)(const void *, const void *))') [-Wincompatible-function-pointer-types]
    5 | void (*foo)(void *, size_t, size_t, int (*)(const void *, const void *, void *), void *) = qsort_r;
      |        ^                                                                                   ~~~~~~~
2 errors generated.