Question

For some reason the following code causes a SIGSEGV when I try to call CFShow_New:

The typedef:

typedef void* (*CFShow_XX)(CFTypeRef lol);

The actual code:

ImageLoaderMachO* loader =
dyld::getDyldImage("/XXX/CoreFoundation");

Symbol cfshow_sym = loader->findSymbol("_CFShow");
CFShow_XX* CFShow_New = (CFShow_XX*)cfshow_sym.nl.n_value;

assert(cfshow_sym.nl.n_value == (uint32_t)CFShow);

CFStringRef str = CFSTR("Test123");

CFShow(str); /* Works */
(*CFShow_New)(str); /* SIGSEGV's */

What could be the issue? CFShow is an extern "C", could that cause it? And if so, how do I fix it?

Answer 1

You defined the pointer to pointer to function do this:

CSShow_XX CFShow_New = (CFShow_XX)cfshow_sym.nl.n_value;

and call:

CSShow_New(str);