From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Edelsohn To: Nick Ing-Simmons Cc: N8TM AT aol.com, richard.earnshaw AT arm.com, gcc AT gcc.gnu.org, espie AT quatramaran.ens.fr, craig AT jcb-sc.com Subject: Re: type based aliasing again Date: Wed, 15 Sep 1999 15:33:00 -0000 Message-id: <9909152233.AA28574@marc.watson.ibm.com> References: <199909151654.RAA05681@tiuk.ti.com> X-SW-Source: 1999-09/msg00657.html >>>>> Nick Ing-Simmons writes: Nick> How about making -fstrict-aliasing implied by -ansi/-iso ;-) This is an interesting and good proposal. The problem that I see is GCC currently uses that flag differently. The flag currently disables GCC extensions that are not allowed by a strictly-conforming ANSI/ISO program. We already have -Os for space optimiation. Maybe we need -Oa or -Oansi or -Oiso for the user to give assurances that the program is standards-compliant. This would allow an umbrella optimization flag to attach many of these optimizations requiring strict conformance to operate correctly. David From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Edelsohn To: Nick Ing-Simmons Cc: N8TM@aol.com, richard.earnshaw@arm.com, gcc@gcc.gnu.org, espie@quatramaran.ens.fr, craig@jcb-sc.com Subject: Re: type based aliasing again Date: Thu, 30 Sep 1999 18:02:00 -0000 Message-ID: <9909152233.AA28574@marc.watson.ibm.com> References: <199909151654.RAA05681@tiuk.ti.com> X-SW-Source: 1999-09n/msg00657.html Message-ID: <19990930180200.Ej29nRgWzoaKkIzU5m15lXH8A4ow93VyneZG9uqDqjI@z> >>>>> Nick Ing-Simmons writes: Nick> How about making -fstrict-aliasing implied by -ansi/-iso ;-) This is an interesting and good proposal. The problem that I see is GCC currently uses that flag differently. The flag currently disables GCC extensions that are not allowed by a strictly-conforming ANSI/ISO program. We already have -Os for space optimiation. Maybe we need -Oa or -Oansi or -Oiso for the user to give assurances that the program is standards-compliant. This would allow an umbrella optimization flag to attach many of these optimizations requiring strict conformance to operate correctly. David