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Re: type based aliasing again
>>>>> "craig" == craig <craig@jcb-sc.com> writes:
craig> I don't know the history of the C aliasing requirement,
craig> but, offhand, it strikes me as highly unlikely that it does
craig> *not* constitute an incompatible change vis-a-vis former
craig> revisions of the standard.
Just to clarify, the language in the standard probably dates to the
original C standard. It is certainly not a new aspect of C9X.
That doesn't have any bearing on our decision about what to do; it's
just a fact. This is not a change to the standard that GCC rushed to
take advantage of; it's a long-standing aspect of ANSI/ISO C.
Compilers just didn't make use of that information until the past few
years, which is why a lot of programs that broke these rules worked
OK historically.
--
Mark Mitchell mark@codesourcery.com
CodeSourcery, LLC http://www.codesourcery.com