change _cdecl for Win32 switch to x64

[dekeenfrance]

Hi,

I wrote a program based on Win32. Now I need to switch it to x64 to be capable to take benefit of x64's computing power. During the switch, there is one thing blocked: some third-part library uses cdecl that cannot be used on x64 anymore. So it cannot compile.

I remember the cdecl is related to calling convention. Please, does anyone know how to fix it so I can run on x64? Thanks!

[dekeenfrance]

Any idea, please?

[dekeenfrance]

please...

[modoran]

What compiler do you use ? With Microsoft Visual Studio On Itanium Processor Family (IPF) and x64 processors, __cdecl is accepted and ignored by the compiler;

http://msdn.microsoft.com/en-us/library/zkwh89ks.aspx
http://en.wikipedia.org/wiki/X86_calling_conventions

[JLBorges]

Right in the beginning of every translation unit, have

#ifdef _M_IA64
    #define __cdecl
#endif // _M_IA64 

Or, alternatively, compile with the preprocessor definition:

/D__cdecl=
See http://msdn.microsoft.com/en-us/library/hhzbb5c8.aspx

[dekeenfrance]

Thanks for your replies. I use VC 2012. But I am not sure about the point related to

Itanium Processor Family

, my CPU is a "i5".

If I understand correctly, the definition

#ifdef _M_IA64
#define __cdecl
#endif // _M_IA64

means to force the x64 compiler to use _cdecl? But I read some articles which explain that VC x64 compiler does not support _cdecl anymore.

What is a translation unit? I am confused. Could someone please help me out?

[dekeenfrance]

any idea please?

[JLBorges]

> If I understand correctly, the definition

> #ifdef _M_IA64
> #define __cdecl
> #endif // _M_IA64 

> means to force the x64 compiler to use _cdecl?

No, it means strip all __cdecl from the translation unit. That is, replace int __cdecl foo(double) with int foo(double)


> What is a translation unit?

A simplified definition would be: every file on which you invoke the C++ compiler driver, with the #includes being expanded.


In short, just knock off all occurrences of __cdecl from all files. Then re-compile and re-link everything - the libraries and your program.

[dekeenfrance]

Thanks for the reply. I have tried with the

_M_IA64

command but it did not work.

Here is the errors indicated by the compiler while I switch from win32 to x64 debug. Always the same.

1>27-9_main.obj : error LNK2019: unresolved external symbol "public: void __cdecl boost::iostreams::file_descriptor::close(void)" ...
1>27-9_main.obj : error LNK2019: unresolved external symbol "public: __int64 __cdecl boost::iostreams::file_descriptor::write(char const *,__int64)" ...
1>27-9_main.obj : error LNK2019: unresolved external symbol "public: class std::fpos<int> __cdecl boost::iostreams::file_descriptor::seek(__int64,int)" ...
1>27-9_main.obj : error LNK2019: unresolved external symbol "public: __cdecl boost::iostreams::file_descriptor_sink::file_descriptor_sink(int,enum boost::iostreams::file_descriptor_flags)" ...
1>27-9_main.obj : error LNK2019: unresolved external symbol "public: __cdecl boost::iostreams::file_descriptor_sink::file_descriptor_sink(class boost::iostreams::file_descriptor_sink const &)" ...
1>27-9_main.obj : error LNK2019: unresolved external symbol "class boost::system::error_category const & __cdecl boost::system::system_category(void)" ...
1>27-9_main.obj : error LNK2019: unresolved external symbol "class boost::system::error_category const & __cdecl boost::system::generic_category(void)" ...

If I am right, is it related to the _cdecl in boost::iostreams and system?

[JLBorges]

> If I am right, is it related to the _cdecl in boost::iostreams and system?

Yes.

You need to rebuild all your libraries for a 64 bit platform with the __cdecl removed. And then you need to have the preprocessor defines before you include any header which was written for a 32 bit platform.

[dekeenfrance]

Do you mean in this case to rebuild boost libraries for x64 ?

[LB]

No, because obviously boost is not part of "all your libraries".

[dekeenfrance]

Well actually I use an external header which includes some boost libraries. While the conversion of my program to x64, the related boost libraries stop the compilation, as I showed above. My own code is ok when I convert to x64 debug. That is why I think I have to rebuild boost for x64.

Am I right?

[LB]

Yes, you need to rebuild boost for 64-bit, I was hoping the sarcasm in my previous post would give you a laugh. I guess I shouldn't push my luck with plain-text.

[dekeenfrance]

Oh, it's ok, no harm.

I already have checked about building boost 1.53 for 64bit. I didn't find an clear instruction to build it. There is a installer for win64, but it occupies 8 Go which is huge. I prefer to build it by myself. Any idea about build it for VC11? Building on 32bit is quite simple but there should be some difference between them.