[PATCH] fixup libobjc usage of PCC_BITFIELD_TYPE_MATTERS

[Trevor Saunders]

On Sun, May 03, 2015 at 10:59:46AM +0200, Andreas Schwab wrote:
> tbsaunde+gcc@tbsaunde.org writes:
> 
> > +AC_DEFUN([gt_BITFIELD_TYPE_MATTERS],
> > +[
> > +  AC_CACHE_CHECK([if the type of bitfields matters], gt_cv_bitfield_type_matters,
> > +  [
> > +    AC_TRY_COMPILE(
> > +      [struct foo1 { char x; char :0; char y; };
> > +struct foo2 { char x; int :0; char y; };
> > +int foo1test[ sizeof (struct foo1) == 2 ? 1 : -1 ];
> > +int foo2test[ sizeof (struct foo2) == 5 ? 1 : -1]; ],
> > +      [], gt_cv_bitfield_type_matters=yes, gt_cv_bitfield_type_matters=no)
> > +  ])
> > +  if test $gt_cv_bitfield_type_matters = yes; then
> > +    AC_DEFINE(HAVE_BITFIELD_TYPE_MATTERS, 1,
> > +      [Define if the type of bitfields effects alignment.])
> > +  fi
> > +])
> 
> gcc/config/aarch64/aarch64.h:#define PCC_BITFIELD_TYPE_MATTERS  1
> 
> configure:11554: /opt/gcc/gcc-20150503/Build/./gcc/xgcc -B/opt/gcc/gcc-20150503/Build/./gcc/ -B/usr/aarch64-suse-linux/bin/ -B/usr/aarch64-suse-linux/lib/ -isystem /usr/aarch64-suse-linux/include -isystem /usr/aarch64-suse-linux/sys-include    -c -O2 -g  conftest.c >&5
> conftest.c:27:5: error: size of array 'foo2test' is negative
>  int foo2test[ sizeof (struct foo2) == 5 ? 1 : -1];
>      ^
> configure:11554: $? = 1

ok, a quick test seems to show Jakub's version of the test works in this
case so lets try that.

Trev

> 
> Andreas.
> 
> -- 
> Andreas Schwab, schwab@linux-m68k.org
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