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Re: gcc unsigned vs signed compare
In article <20110831202534.GA7800%antioche.eu.org@localhost>,
Manuel Bouyer <bouyer%antioche.eu.org@localhost> wrote:
>I tracked down a bug on a mips64el platform (see PR 45310), which turns out
>to be a signed vs unsigned compare issue.
>In lib/libc/gen/fixunsgen_ieee754.c there is a compare:
> (exp - mant_dig > sizeof(UINTXX_T)*8-1)
>exp is int, mant_dig is size_t (unsigned long) and sizeof returns size_t.
>gcc generates an unsigned compare for this, which doesn't gives the expected
>result when exp < mant_dig. Is gcc right when generating an unsigned
>compare here ?
Yes, the promotion rule is signed -> unsigned.
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