Re: [Mingw-users] gcc cc1plus bug

[Keith M. <kei...@to...>]

Sisyphus wrote, quoting me:
>> `--host=x --build=y' is the standard autoconf way to initiate a
>> cross-compile.  The purist in me says that, if you use this method
>> of specifying the host compiler, then you should *not* need to use
>> `-mno-cygwin' at all.  I did try it once upon a time[1], and IIRC,
>> this is in fact the case.
>>
>> Conversely, if you use CC='gcc -mno-cygwin', and friends, you should
>> not need `--host', (nor `host_alias'), nor `--build', IIRC.
>>
>> `host_alias=i686-pc-mingw32' is completely redundant here; configure
>> sets it internally anyway, to identically the same value as you give
>> with `--host'.
>
> On the strength of that I initially tried to build a static build of
> GMP-4.2.1 by running:
>
> ./configure --disable-shared --enable-static CC='gcc -mno-cygwin'
>
> But that produced the following error almost immediately:
>
> ----------------------------------------------
> Rob@desktop2 /cygdrive/c/cygwin/comp/mingw/gmp/static/gmp-4.2.1
> $ ./configure --disable-shared --enable-static CC='gcc -mno-cygwin'
> -pc' not recognizede `x86_64. Invalid configuration `x86_64
> -pc-cygwin failed /bin/sh ./config.sub x86_64

That appears anomalous.  Aren't you running a 32-bit OS emulation, even
though your hardware is 64-bit?  If that is true, then the default host
identification, as provided by Cygwin to the configure script for the
emulated 32-bit host, is flawed.

OTOH, if you really are running a 64-bit Cygwin, then maybe the kludgy
way in which -mno-cygwin invokes the cross-compile to the mingw32 host
breaks in that environment.  Setting up a proper cygwin-cross-mingw32
tool chain, invoked by the standard autoconf semantics, may be the way
you should go.  (Don't ask me why the Cygwin folks chose this kludgy
-mno-cygwin way, in the first place).

If you wish to pursue this further, please take it up on a Cygwin ML.

Regards,
Keith.