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Re: type based aliasing again


>>>>> Nick Ing-Simmons writes:

Nick> But the math standard has had much longer to settle in and get adopted
Nick> in the existing code base. When new C alias standard has been around as long
Nick> as IEEE-754 then it may be time to flip the default...

	The recent C Standard allows the optimization but does not require
a specific behavior.  If it specified a behavior, then this would not be
an optimization.  As the behavior of this construct is undefined, this
transformation should not be enabled without explicit request from the
user.

	The FSF has stated, only just recently, that not breaking existing
programs because of undefined behavior is a goal that GCC should try to
meet.  Removing -fstrict-aliasing is a simple change that will meet this
goal and not dimish the functionality of this optimization for those who
want to invoke it explicitly.

	I think that GCC should make this simple change.

David


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