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Hi,

I have a question regarding the ampersand-operator.
I want to store the address of a class-member-function in an void *pointer (not in an class-member-pointer).
(the function is not virtual so no vtable stuff etc to think of)

I wonder why this:

void *blub2 = (void *)&CVictim::MemFunc;

does NOT compile, but this:

void *blub  = (void *&)CVictim::MemFunc;

does.

Also i wonder why when I use a dirty union cast:

union {
  void *pFunc;
  void (CVictim::*mFunc)();
} weldPointers;
weldPointers.mFunc = &CVictim::MemFunc;
void *blub3 = weldPointers.pFunc;

it doesnt give the same result than blub.

Thanks in advance.

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Edit:

I also wonder why it is possible to use the reference operator 2 times in this case:

void **blub4  = &(void *&)CVictim::MemFunc;

[BAILOPAN]

Read this for an in-depth explanation of member function pointers: http://www.codeproject.com/KB/cpp/FastDelegate.aspx

Gist is that when you get a member function pointer you have a complex, compiler-dependent structure -- the language just doesn't guarantee that you can deref it back to an address.

SourceHook can do some decoding for you - probably only virtual calls at the moment though. See SourceHook::GetFuncInfo (and then you can use standard vtable inspection (or SH_GET_ORIG_VFNPTR_ENTRY in MM:S 1.6+ API).

Otherwise, see Don Clugston's excellent article for the structures each compiler uses.