c - Function pointers - outside library, warning: initialization from incompatible pointer type -

with yours compiled code function pointers. exact same thing functions "outside" library. typedef, arguments, compilation flags 100% fine, got warning when try call function outside library (when wrote function same prototype , tried call code fine). ideas?

#include <stdio.h> #include <stdlib.h> #include "libs/outlib.h"  typedef int (*vfuncv)(int, double);  void call(int which, vfuncv* fun, int a, double b) {     fun[which](a, b); }  int main() {     vfuncv fun[2] = {outlibfun1, outlibfun2};      call(0, fun, 3, 4.5);     return 0; } 

warning:

funargs.c: in function ‘main’: funargs.c:14:5: warning: initialization incompatible pointer type [enabled default] funargs.c:14:5: warning: (near initialization ‘fun[0]’) [enabled default] funargs.c:14:5: warning: initialization incompatible pointer type [enabled default] funargs.c:14:5: warning: (near initialization ‘fun[1]’) [enabled default] 

and 14th line:

vfuncv fun[2] = {outlibfun1, outlibfun2}; 

declaration of outlibfun: int outlibfun1(int, double);

another not-working (warning) example:

#include <stdio.h> #include <stdlib.h> #include "libs/outlibz2.h"  typedef unsigned char* (*vfuncv)(const unsigned char *, unsigned long, unsigned char *);  void call(int which, vfuncv* fun, const unsigned char *a, unsigned long b, unsigned char * c) {     fun[which](a, b, c); }  int main() {     vfuncv fun[2] = {outlibfun1};      call(0, fun, "b", 3, "a");     return 0; } 

if function isn't declared in same source , before assigning function pointer need extern declaration like

extern int outlibfun1( int, double ); 

in case should have them in libs/outlib.h