From 852b81bbe00b28c8a472c148c8fc84f6ecee9c3b Mon Sep 17 00:00:00 2001 From: Michael Meissner Date: Wed, 20 Mar 2002 22:56:33 +0000 Subject: Clarify that -O2 sets -fstrict-aliasing From-SVN: r51097 --- gcc/ChangeLog | 5 +++++ gcc/doc/invoke.texi | 12 ++++++++---- 2 files changed, 13 insertions(+), 4 deletions(-) (limited to 'gcc') diff --git a/gcc/ChangeLog b/gcc/ChangeLog index a399429..2a071c3 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2002-03-20 Michael Meissner + + * doc/invoke.texi (Optimize Options): Document that -O2 sets + -fstrict-aliasing. + 2002-03-20 Bob Wilson * config/xtensa/xtensa.h (ASM_OUTPUT_POOL_PROLOGUE): Emit a diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi index abb9638..52af61d 100644 --- a/gcc/doc/invoke.texi +++ b/gcc/doc/invoke.texi @@ -3170,10 +3170,11 @@ perform loop unrolling or function inlining when you specify @option{-O2}. As compared to @option{-O}, this option increases both compilation time and the performance of the generated code. -@option{-O2} turns on all optional optimizations except for loop unrolling, -function inlining, and register renaming. It also turns on the -@option{-fforce-mem} option on all machines and frame pointer elimination -on machines where doing so does not interfere with debugging. +@option{-O2} turns on all optional optimizations except for loop +unrolling, function inlining, and register renaming. It also turns on +the @option{-fforce-mem} and @option{-fstrict-aliasing} option on all +machines and frame pointer elimination on machines where doing so does +not interfere with debugging. Please note the warning under @option{-fgcse} about invoking @option{-O2} on programs that use computed gotos. @@ -3716,6 +3717,9 @@ node, an alias set for the node. Nodes in different alias sets are not allowed to alias. For an example, see the C front-end function @code{c_get_alias_set}. +For all machines, optimization level 2 and higher enables this flag by +default. + @item -falign-functions @itemx -falign-functions=@var{n} @opindex falign-functions -- cgit v1.1