From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Lehmann To: gcc AT gcc.gnu.org Subject: Re: type based aliasing again Date: Tue, 14 Sep 1999 17:22:00 -0000 Message-id: <19990915021343.O3983@cerebro.laendle> References: <9909141656.AA20910@marc.watson.ibm.com> X-SW-Source: 1999-09/msg00569.html On Tue, Sep 14, 1999 at 12:56:26PM -0400, David Edelsohn wrote: > I think that -ffast-math and the behavior of compilers from other > vendors is good precedent that -fstrict-aliasing should be removed from > the standard -O# optimization levels and accessed orthogonally. I think > that I and the other members of the GCC Steering Committee had good > intentions, but were mistaken about the impact of including this > optimization in a -O# level. But have we seen much impact yet (disregarding what people *think* should be done?). Also the issue seems not to be aliasing as such, but that aliasing might break cases where there is no benefit in doing so. -- -----==- | ----==-- _ | ---==---(_)__ __ ____ __ Marc Lehmann +-- --==---/ / _ \/ // /\ \/ / pcg@goof.com |e| -=====/_/_//_/\_,_/ /_/\_\ XX11-RIPE --+ The choice of a GNU generation | | From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marc Lehmann To: gcc@gcc.gnu.org Subject: Re: type based aliasing again Date: Thu, 30 Sep 1999 18:02:00 -0000 Message-ID: <19990915021343.O3983@cerebro.laendle> References: <9909141656.AA20910@marc.watson.ibm.com> X-SW-Source: 1999-09n/msg00569.html Message-ID: <19990930180200.uKat1DTC-GpfaxAFRdQ2-ynDxnnkApdUCw0eu1gredc@z> On Tue, Sep 14, 1999 at 12:56:26PM -0400, David Edelsohn wrote: > I think that -ffast-math and the behavior of compilers from other > vendors is good precedent that -fstrict-aliasing should be removed from > the standard -O# optimization levels and accessed orthogonally. I think > that I and the other members of the GCC Steering Committee had good > intentions, but were mistaken about the impact of including this > optimization in a -O# level. But have we seen much impact yet (disregarding what people *think* should be done?). Also the issue seems not to be aliasing as such, but that aliasing might break cases where there is no benefit in doing so. -- -----==- | ----==-- _ | ---==---(_)__ __ ____ __ Marc Lehmann +-- --==---/ / _ \/ // /\ \/ / pcg@goof.com |e| -=====/_/_//_/\_,_/ /_/\_\ XX11-RIPE --+ The choice of a GNU generation | |