From mboxrd@z Thu Jan 1 00:00:00 1970 From: Martin Kahlert To: egcs@cygnus.com Subject: Re: x86 double alignment (was egcs-1.1 release schedule) Date: Mon, 29 Jun 1998 05:20:00 -0000 Message-id: <19980629141934.A18433@keksy.mchp.siemens.de> References: <19980624192457.45730@cerebro.laendle> <199806251615.MAA12029@melange.gnu.org> <19980628214914.40045@cerebro.laendle> X-SW-Source: 1998-06/msg01046.html Quoting Marc Lehmann (pcg@goof.com): > On Thu, Jun 25, 1998 at 12:15:17PM -0400, Craig Burley wrote: > > >The original patch turned on -mstack-align-double, which I thought is safe, > > >but it isn't. I got a report from a windows user that it breaks most windows > > >function semantics, as these functions deallocate the stack themselves. In > > >this case, -mstack-align-double will break the program. > > > > Wait, how can these functions deallocate the stack themselves when > > the *caller* also is deallocating the stack, as is normally the > > it isn't: __attribute__((stdcall)). > > > case for x86-ABI code? Aren't these functions essentially violating > > the ABI in a way the compiler producing code that calls them *must* > > know about? > > the problem is we can't change the windows kernel. its a third-party > product I'd really like to recompile ;) > A small dummy question: Is it possible without big efford, to only align automatic (local) double vars and leave all function parameters untouched? So no ABI gets violatet. Most time critical calculations aren't performed on stack doubles, i would imagine. Just a silly question. Bye, Martin. -- What is the difference between Jurassic Park and Microsoft? One is an over-rated high tech theme park based on prehistoric information and populated mostly by dinosaurs, the other is a Steven Spielberg movie.