meson dummy with two source files

foo.c

int increment(int x) {
    return x+1;
}

main.c

#include <stdio.h>
#include "foo.c"

int main() {
	int bar = increment(42);
	printf("Hello: %d\n", bar);
	return 0;
}

meson.build

project('hello-world', 'c')
executable('hello', sources: ['main.c'])