FIX: Relocations Not Generated For Array of Ptrs To Functions Using Typedefs

ID: Q216716


The information in this article applies to:


SYMPTOMS

Relocations are not generated for typdefed pointers (or arrays) to a typedef of a function pointer. This leads some pointers to incorrect locations.


RESOLUTION

Two levels of typedef's are required to encounter this bug. One workaround is to use only one typedef to alias the pointer to function type.


STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article.

This bug was corrected in Visual Studio 6.0 Service Pack 3. For more information about Visual Studio service packs, please see the following articles in the Microsoft Knowledge Base:

Q194022 INFO: Visual Studio 6.0 Service Packs, What, Where, Why

Q194295 HOWTO: Tell That Visual Studio 6.0 Service Packs Are Installed


MORE INFORMATION

Steps to Reproduce Behavior


#include <stdio.h>
struct S{
    int m_x;
    int m_y;
};

S f() {
	return S();
}

typedef S (Func_t)();
typedef Func_t *pFunc_t;
typedef int (* PFUNC)();

pFunc_t	pFunc1	= &f;
PFUNC *	ppFunc1	= reinterpret_cast<PFUNC *>( &pFunc1 );

pFunc_t	pFunc2	= 0;
PFUNC *	ppFunc2	= reinterpret_cast<PFUNC *>( &pFunc2 );

int main()
{
	pFunc_t	pFunc3	= &f;
	PFUNC *	ppFunc3	= reinterpret_cast<PFUNC *>( &pFunc3 );

	pFunc_t	pFunc4	= 0;
	PFUNC *	ppFunc4	= reinterpret_cast<PFUNC *>( &pFunc4 );

	printf("pFunc1  = 0x%08x\n", pFunc1);
	printf("ppFunc1 = 0x%08x\n", ppFunc1);
	printf("pFunc2  = 0x%08x\n", pFunc2);
	printf("ppFunc2 = 0x%08x\n", ppFunc2);
	printf("pFunc3  = 0x%08x\n", pFunc3);
	printf("ppFunc3 = 0x%08x\n", ppFunc3);
	printf("pFunc4  = 0x%08x\n", pFunc4);
	printf("ppFunc4 = 0x%08x\n", ppFunc4);

	return 0;
} 
The addresses in the following output may vary:

pFunc1  = 0x00401005
ppFunc1 = 0x00401005
pFunc2  = 0x00000000
ppFunc2 = 0x00000000  Shouldn't be 0
pFunc3  = 0x00401005
ppFunc3 = 0x00401005
pFunc4  = 0x00000000
ppFunc4 = 0x00000000  Shouldn't be 0 

Additional query words:


Keywords          : kbservicepack kbCompiler kbCPPonly kbVC600bug kbVC600fix kbVS600sp2 kbVS600SP1 kbVS600sp3fix 
Version           : winnt:6.0
Platform          : winnt 
Issue type        : kbbug 

Last Reviewed: May 19, 1999