[patch] Enable fmove-loop-invariants by default

[Joseph S. Myers]

On Sun, 26 Feb 2006, Mark Mitchell wrote:

> Richard Guenther wrote:
> 
> > We should at least deprecate them (and maybe warn, if not -Werror) so we
> > can get rid of them in 4.3.
> 
> I think we should probably accept them forever more.  As Daniel says,
> there is a ton of code out there passing -fno-strength-reduce, and it
> does us no harm just to keep accepting those options.

Indeed, these are options with no intended effect on code semantics or 
diagnostics, so accepting forever is harmless.  It's options with semantic 
effect (e.g. enabling non-standard extensions we've now removed) that 
should give errors for being no longer valid.  The code using 
-fno-strength-reduce is probably using it because of superstition about an 
old GCC 2.7 bug (see <http://gcc.gnu.org/ml/gcc/1997-09/msg00920.html> for 
the testcase), not for any semantic effect other than "avoid this old 
bug".

-- 
Joseph S. Myers               http://www.srcf.ucam.org/~jsm28/gcc/
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