[OT] Prevent linker from unnecessary symbol resolution

[Ian Lance Taylor]

Srikanth Madani <srikanth.madani@vodafone.com> writes:

> Suppose I have a C file fun1.c containing two functions:
> 
> __________
> void func1() {
>         printf("\nIn function func1()\n");
> }
> void func2() {
>         func3();
> }
> ___________
> 
> and another called hello.c containing:
> 
> ___________
> void main() {
>           func1();
> }
> ___________
> 
> Is it possible to create a staticly linked binary using just these two
> source files? Or do I have to provide a function definition for func3(),
> even though it is not called.

You have to define func3.  You could do it on the linker command line
using something along the lines of '-Wl,--defsym,func3=0'.

If you compile with -ffunction-sections and link with --gc-sections,
you might get away with not defining func3.  I haven't tried it,
though, and it would be inherently system dependent.

Ian