gettext contains libintl.h. That header file defines a macro that replaces
`setlocale` by `libintl_setlocale`. That function eventually calls the original
`setlocale()` from Apple's libc, but is known to make it fail.
Mac users with gettext from Homebrew can easily reproduce this:
#include <stdio.h>
#include <locale.h>
#include <libintl.h>
int main(void) {
setlocale(LC_ALL, "");
printf("locale: %s\n", setlocale(LC_CTYPE, NULL));
}
Compile and run it:
cc -I/usr/local/opt/gettext/include -L/usr/local/opt/gettext/lib -lintl -o test test.c && ./test
When $LC_CTYPE is set to a valid value like UTF-8, it should output:
locale: UTF-8
But it does not. It returns C anyway. Remove libintl.h and recompile and you get
the expected UTF-8.
Fixes https://github.com/neovim/neovim/issues/9787
Assuming `inline` is there for a reason, so it is kept and function was moved to
typval.h and not to typval.c which does not have problems with #including
message.h.
