Re: i686 ld couldn't resolve wglCreateContext from libopengl32.a on x86_64 system

[Yaakov Selkowitz <yselkowitz at cygwin dot com>]

On 2017-03-02 18:14, sorryforaskingthis.bk.ru via cygwin wrote:
> > On 2017-03-02 16:54, Yaakov Selkowitz <yselkowitz@cygwin.com> wrote:
> >
> > This looks like a snippet of an autoconf AC_CHECK_LIB (or
> > AC_CHECK_FUNCTION) test. Such tests don't work with 32-bit Win32 APIs
> > -- on either Cygwin or MinGW -- because they don't take stdcall into
> > account. You'll need to modify the test to work around that.
> >
> > Also, if you're using Cygwin, do you *really* want to be using Win32
> > OpenGL and not X11?
> Yes, you're right. It's autoconf test and it perfectly passed at 64-bit MinGW
> and 64-bit Cygwin, but not on 32-bit Cygwin.

It would fail on 32-bit MinGW too.

> And I don't understand why you're say that it is related to stdcall, while
> wglCreateContext exposed directly without any @0 @4 etc.

No, it's not, check the implib yourself.  You have to use a proper 
declaration to link stdcall functions, and the autoconf tests don't do 
that.  You need to change the test to avoid this; exactly how depends on 
the intent of the test.

> Yes, I need to use Win32.
         ^^^^
> I want to port application that heavily POSIX-dependent, but also want to save
                                                                    ^^^^
> performance as much as possible.

Big difference.

> I think if w32api-runtime package is provided it supposed to work.

Maybe, maybe not.  Mixing *NIX and Win32 APIs isn't so simple.

--
Yaakov

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