Re: [PATCH v2] fix Ada bootstrap on Cygwin64 (PR bootstrap/94918)

[Arnaud Charlet <charlet@adacore.com>]

> > > > This fixes a compilation error preventing bootstrap with Ada on
> > > > x86_64-pc-cygwin. See PR bootstrap/94918 for details.
> > > >
> > > > Compared to the initial patch sent in May 2020, this v2 patch places
> > > > the fix in Ada's raise-gcc.c instead of the shared unwind-generic.h,
> > > > which should hopefully simplify getting it applied.
> > >
> > > Not sure why. Applying it there looks incomplete and kludgy, don't you
> > > agree?
> >
> > Ok, then here's v3 which places the fix in unwind-generic.h. The fix
> > matches what Ada's mingw32.h does.
> >
> > Tested by bootstrapping this and the preliminary workaround for
> > PR98590 on x86_64-pc-cygwin.
> >
> > Ok for master and branches?
> 
> Ping. This is currently the only blocker for bootstrapping gcc-11 with
> Ada on Cygwin64.

Unfortunately changes in libgcc are outside my area, you'll need to find
another maintainer for this one.

> > libgcc/
> >
> > 2021-01-10  Mikael Pettersson  <mikpelinux@gmail.com>
> >
> >         PR bootstrap/94918
> >         * unwind-generic.h (__SEH__): Prevent windows.h from including
> >         x86intrin.h or emmintrin.h on Cygwin64.
> >
> > --- gcc-11-20210103/libgcc/unwind-generic.h.~1~ 2021-01-03
> > 23:32:20.000000000 +0100
> > +++ gcc-11-20210103/libgcc/unwind-generic.h     2021-01-09
> > 14:51:16.262378715 +0100
> > @@ -30,6 +30,12 @@
> >
> >  #if defined (__SEH__) && !defined (__USING_SJLJ_EXCEPTIONS__)
> >  /* Only for _GCC_specific_handler.  */
> > +#if defined (__CYGWIN__) && !defined (__CYGWIN32__) && !defined (IN_RTS)
> > +/* Note: windows.h on cygwin-64 includes x86intrin.h which uses malloc.
> > +   That fails to compile, if malloc is poisoned, i.e. if !IN_RTS.  */
> > +#define _X86INTRIN_H_INCLUDED
> > +#define _EMMINTRIN_H_INCLUDED
> > +#endif
> >  #include <windows.h>
> >  #endif
>