[patch]: Add configure and required host/target definitions for new cygwin x64 target

[Dave Korn]

On 23/03/2013 00:41, Kai Tietz wrote:
> 2013/3/23 Dave Korn <dave.korn.cygwin@gmail.com>:
>> On 22/03/2013 09:56, Kai Tietz wrote:
>>> Hi,
>>>
>>> this patch adds required configure changes for new cygwin x64 target.
>>> Index: gcc/configure.ac
>>> ===================================================================
>>> --- gcc/configure.ac  (Revision 196898)
>>> +++ gcc/configure.ac  (Arbeitskopie)
>>> @@ -3623,7 +3623,7 @@ changequote([,])dnl
>>>       # wrappers to aid in interposing and redirecting operators new, delete,
>>>       # etc., as per n2800 #17.6.4.6 [replacement.functions].  Check if we
>>>       # are configuring for a version of Cygwin that exports the wrappers.
>>> -     if test x$host = x$target; then
>>> +     if test x$host = x$target && test x$host_cpu = xi686; then
>>>         AC_CHECK_FUNC([__wrap__Znaj],[gcc_ac_cygwin_dll_wrappers=yes],[gcc_ac_cygwin_dll_wrappers=no])
>>>       else
>>>         # Can't check presence of libc functions during cross-compile, so
>>   Rather than just bailing on x86_64, shouldn't this code check for the
>> presence of one of the 64-bit versions of the C++ wrapper functions such as
>> __wrap__Znam instead?
> 
> Sure, this should be a follow-up patch.  For now we should get initial
> version into repository.  There are some other places we need to visit
> later, too.

  Ok, fair enough.

>>> Index: libgcc/config.host
>>> ===================================================================
>>> --- libgcc/config.host        (Revision 196898)
>>> +++ libgcc/config.host        (Arbeitskopie)
>>> @@ -564,13 +564,30 @@ i[34567]86-*-cygwin*)
>>>               tmake_eh_file="i386/t-dw2-eh"
>>>       fi
>>>       # Shared libgcc DLL install dir depends on cross/native build.
>>> -     if test x${build} = x${host} ; then
>>> +     if test x${host} = x${target} ; then
>>   I don't get this.  We're compiling a target library, so only build and host
>> are correct to use, AIUI; $target may still be set by accident, but it's not
>> meaningful when building a target lib.
> 
> Well, I think the idea here was that cygwin installs anyway
> (especially for candian-cross AFAIR) into native (bin/) location.
> That's a kludge.

  Eh?  The whole point of this bit is to avoid installing into the native
location in any kind of cross build.  This was the fix for PR40125; the libgcc
equivalent of $srcdir/config/lthostflags.m4.

    cheers,
      DaveK