cc -pipe -O   -pthread  -Wall -Wextra -Werror -Wno-error=deprecated -Wno-error=deprecated-declarations dirent/size_t.c -o dirent/size_t -D_POSIX_C_SOURCE=202405L  -lm -lpthread -lrt  -lrt -lcrypt
dirent/size_t.c:2:1: error: unknown type name 'size_t'
 size_t* foo;
 ^~~~~~
dirent/size_t.c:2:1: note: 'size_t' is defined in header '<stddef.h>'; did you forget to '#include <stddef.h>'?
+#include <stddef.h>
 size_t* foo;
 ^~~~~~