CMake/Modules/CheckVariableExists.c

#ifdef CHECK_VARIABLE_EXISTS

extern int CHECK_VARIABLE_EXISTS;

#ifdef __CLASSIC_C__
int main(){
  int ac;
  char*av[];
#else
int main(int ac, char*av[]){
#endif
  if(ac > 1000){return *av[0];}
  return CHECK_VARIABLE_EXISTS;
}

#else  /* CHECK_VARIABLE_EXISTS */

#  error "CHECK_VARIABLE_EXISTS has to specify the variable"

#endif /* CHECK_VARIABLE_EXISTS */
ENH: Added CHECK_VARIABLE_EXISTS macro. 2002-11-21 10:11:46 -05:00			`#ifdef CHECK_VARIABLE_EXISTS`

			`extern int CHECK_VARIABLE_EXISTS;`

ENH: fix tests for non-ansi c on hp and remove warnings for ansi c 2004-04-15 08:22:19 -04:00			`#ifdef __CLASSIC_C__`
			`int main(){`
			`int ac;`
			`char*av[];`
			`#else`
			`int main(int ac, char*av[]){`
			`#endif`
			`if(ac > 1000){return *av[0];}`
BUG#502: Do not let optimizing compilers think the symbol exists. Require the symbol by making the return value depend on it to force linking. 2004-04-26 10:19:44 -04:00			`return CHECK_VARIABLE_EXISTS;`
ENH: Added CHECK_VARIABLE_EXISTS macro. 2002-11-21 10:11:46 -05:00			`}`

			`#else /* CHECK_VARIABLE_EXISTS */`

			`# error "CHECK_VARIABLE_EXISTS has to specify the variable"`

			`#endif /* CHECK_VARIABLE_EXISTS */`