C++ 的 64 位名称修改

Question

I have a bit of code which has the following line

  #pragma comment(linker, "/include:_test@12") 

The project which uses this code works fine when I compile the code using C++ Visual Studio 2010 with configuration type 32bit (I am also on a 32 bit windows machine).

I get a link error when I change the machine to 64bit and use x64 configuration which compiling with C++ Visual Studio 2010.

Is C++ name mangling different for 32bit vs 64bit? If so, where can I find the 64bit C++ name mangling conventions?

Answer 1

Yes the name mangling is different between 32 and 64 bit. A reasonable article covering the exact formats can be found here . You can tell the major differences pretty quickly, however, by simply compiling to both targets and examining the resulting map files. From my experience they're almost identical (64bit adds a small datum, potentially changes others).

Simple sample: void foo();

32bit: ?foo@A@@QAEXXZ
64bit: ?foo@A@@QEAAXXZ

For non-mangled std call, the length suffix can be substantially different, depending on the parameter stack usage. The default 64-bit settings for VC++ do not prepend underscores nor does it encode length-suffixes. The following was compiled both 32/64bit configs with pure out-of-the-box settings:

extern "C" int _stdcall func2(int, int, char*);

32bit: _func2@12
64bit: func2

Not much point there, is there.

Completing the circuit, unmangled _cdecl, which does this:

extern "C" int _cdecl func2(int, int, char*);

32bit: _func2
64bit: func2

If it seems like they went out of their way to make you know what you're pulling-in or exporting-out, evidence suggests you're probably correct.