[64 bit] problem using Win32 API in native Cygwin64 library

Corinna Vinschen corinna-cygwin@cygwin.com
Tue Apr 2 15:37:00 GMT 2013

On Apr  2 13:19, Corinna Vinschen wrote:
> Hi Václav,
> On Apr  2 12:25, Václav Zeman wrote:
> > Hi.
> > 
> > I have tried to compile the log4cplus library on Cygwin64. Compilation
> > goes fine but linking ends with error.
> > [...]
> > src/.libs/liblog4cplus_la-cygwin-win32.o: In function `VarCmp':
> > /usr/include/w32api/oleauto.h:487: undefined reference to `VarCmp'
> > /usr/include/w32api/oleauto.h:487:(.text+0x34f): relocation truncated
> > to fit: R_X86_64_PC32 against undefined symbol `VarCmp'
> > src/.libs/liblog4cplus_la-cygwin-win32.o: In function `_InterlockedAdd':
> > /usr/include/w32api/winnt.h:1452: undefined reference to
> > `_InterlockedExchangeAdd'
> > [...]
> Thanks for the report.  That's apparently a bug in the Cygwin w32api
> implementation of the mingw libs.  On 64 bit, a lot of simple functions
> of the w32api, or functions used under the hood of inline functions, are
> implemented as compiler intrinsics in the Microsoft Visual compilers.
> These compiler intrinsics don't exist in gcc, therefore they are
> implemented as library functions in Mingw-w64.  Unfortunately they are
> implemented in libmingwex.a right now, which is not included in the
> Cygwin w32api.
> I'm going to fix that today, so that the intrinsics will be exported
> by libkernel32.a instead.  This allows Cygwin applications to access
> them as well.
> Stay tuned.

I just uploaded a new w32api package which should fix this issue.
The intrinsics are now provide by libkernel32.a.  Please give it
a try.


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Maintainer                 cygwin AT cygwin DOT com
Red Hat

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