Linker Error when using TARGET_IPHONE_SIMULATOR in C++

Question

The TARGET_IPHONE_SIMULATOR macro does not work in the C++ source I added to the project. Though it should be noted that the code runs if I simply change out the macro with a 1 or a 0.

So here's the setup. I've been converting the files from : https://code.google.com/p/ld48jovoc/source/browse/util/tweakval/?r=13 to work with the iOS application I'm making in XCode.

Everything is pretty much the same except for the header.

#ifndef TWEAKVAL_H
#define TWEAKVAL_H

#ifdef __cplusplus
extern "C" {
#endif

#include <sys/types.h>

// Do only in debug builds on simulator, this does NOT work on iOS device
#if TARGET_IPHONE_SIMULATOR // replace with 1 or zero to make it work
#  define TV_USE_TWEAKVAL 1
#else
#  define TV_USE_TWEAKVAL 0
#endif


//
// See the thread referenced above for idea of how to implement
// this without the __COUNTER__ macro.

// If we are in a build modethat wants tweakval, and the compiler
// supports it, use it
#if TV_USE_TWEAKVAL
#  define _TV(Val) _TweakValue( __FILE__, __COUNTER__, Val )

//float _TweakValue( const char *file, size_t counter, float origVal );
int _TweakValue( const char *file, size_t counter, int origVal );

void ReloadChangedTweakableValues();

#else
// don't use it
#  define _TV(Val) Val
#  define ReloadChangedTweakableValues()

#endif

#ifdef __cplusplus
}  // extern "C"
#endif

#endif

the cpp file is nearly identical except the whole thing is wrapped in #if TV_USE_TWEAKVAL.

Now I could set this macro manually, via code or in the build settings but I'd prefer to get this thing to automatically enable/disable via detecting the preprocessor command. My guess is that macro is not getting detected when it links the tweakval source code and I don't know what build settings I need to change to fix this issue.

Thanks.

Answer 1

TARGET_IPHONE_SIMULATOR comes from TargetConditionals.h . You need to #include that file. Presumably your other code gets it indirectly via some other path like Cocoa/Cocoa.h .