[Bug bootstrap/50342] gcc/configure fails on Mac OS X Lion/Xcode 4.1 with recent GCCs

["simon at pushface dot org" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50342

--- Comment #5 from simon at pushface dot org 2011-09-09 18:46:46 UTC ---
(In reply to comment #4)
> > Other than only building ada triggers the bug.
> 
> Huh?  How could Ada have something to do with the toplevel configure?

The problem only happens in gcc/configure (well, perhaps in other lower-level
configures too).

It happens because if Ada's involved you must use an Ada-capable compiler, i.e.
(FSF) GCC. For other languages, the response to this PR would rightly be "so
use Apple's compiler".

Is there an approved way of getting CFLAGS="-D_FORTIFY_SOURCE=0" into the
configure process? (there isn't AFAICT a problem with the actual build). I've
tried

  ../gcc-4.6.1/configure host_configargs="CFLAGS=\"-D_FORTIFY_SOURCE=0\"" .....

which seems to work but is I think undocumented? (and hairy)

On the other hand, we could reconsider -fkeep-inline-functions in the configure
scripts? The problem arises because the unsupported inlined builtin call is
(effectively) in <string.h>, so we don't need to actually call it.