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Re: basic-improvements merge status


>>>>> Zack Weinberg writes:

Zack> David Edelsohn <dje@watson.ibm.com> writes:
>> Any idea what change in GCC 3.4BIB is causing GCC to "optimize"
>> 
>> (float) sin(x)
>> 
>> as
>> 
>> sinf(x)?

Zack> I remember such an optimization being implemented but I can't find the
Zack> change log entry for it.  My recollection is that it was Jan Hubicka
Zack> who coded it.  Jan?

	Yes, it appears to be due to the builtins.def changes by Jan which
assumes that all of those functions natively are available on every
target.  One cannot make that assumption.  Testing for the existence of
those functions on the target is not easy.

	In most cases, the transformation will result in a linker error on
systems which do not provide the function, but libstdc++-v3 graciously
provides the symbols, creating a recursion in those definitions.

David


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