Question

I have the following files:

main.c :

int f(void);  
int main(void)
{
    f();
    return 0;
}

f.c:

char *f = "linker";

GNUMakefile:

CC = gcc
CFLAGS = -Wall -g

all: main

main: main.o f.o

main.o: main.c
f.o: f.c

clean:
    rm -rf *.o main

When running the makefile I get no compilation warnings/errors. Why?

Answer 1

Because you lied to the compiler … and it trusts you.

In main.c you told the compiler f is a function (declaration / prototype), but f is, in fact, a pointer to a (unmodifiable) character array of length 7 defined in f.c (definition).

Don’t lie to the compiler.