GCC can't find stdio.h in Alpine Linux

Question

In a fresh Alpine Linux I installed GCC by

apk add --update-cache gcc

but still a simple program

#include <stdio.h>

int main(int argc, char *argv[]) {
    return 0;
}

compiled with message

fatal error: stdio.h: No such file or directory

Answer 1

Install libc-dev in addition to GCC, or just install build-base for everything (alpine-sdk is probably an overkill). To install run the following command:

apk add libc-dev

You need to install it separately because in Alpine Linux, the package GCC doesn't depend on libc-dev for good reason:

You can use gcc to compile things without libc, for example hypervisors firmware etc.

And August Klein also noted that in Debian, GCC only recommends libc-dev for the same reason (but most people don't do --no-install-recommends anyway).