[Bug tree-optimization/48766] [4.4/4.5/4.6/4.7 Regression] Infinite recursion in fold_binary_loc()

["joseph at codesourcery dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48766

--- Comment #8 from joseph at codesourcery dot com <joseph at codesourcery dot com> 2011-12-06 20:12:12 UTC ---
On Tue, 6 Dec 2011, iant at google dot com wrote:

> http://gcc.gnu.org/bugzilla/show_bug.cgi?id=48766
> 
> --- Comment #7 from iant at google dot com <iant at google dot com> 2011-12-06 18:40:58 UTC ---
> > I don't know about -fstrict-overflow, but maybe that should be separate 
> > (controlling whether, in cases where the default semantics are in effect, 
> > certain optimizations relating to overflow are made).
> 
> That was my intent for -fno-strict-overflow: it does not change the
> semantics, it just disables optimizations.  Of course when -fwrapv or
> -ftrapv are set, overflow behaviour is defined, so -fno-strict-overflow
> does nothing.  -fno-strict-overflow is only meaningful when neither
> -fwrapv nor -ftrapv are set.

As I understand it, -fno-strict-overflow also affects optimizations for 
pointer overflow in any of the three -fwrapv/-ftrapv/default modes (those 
modes only relate to integer arithmetic semantics, not anything for 
pointer arithmetic).