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Re: [PATCH 1/8] Document signaling for min, max and ltgt operations
On Tue, Aug 20, 2019 at 11:18:38AM +0200, Ilya Leoshkevich wrote:
> Currently it's not clear whether or not min, max and ltgt should raise
> floating point exceptions when dealing with qNaNs.
> Right now a lot of code assumes that LTGT is signaling: in particular,
> it's generated for ((x < y) || (x > y)), which is signaling. The
> behavior of MIN/MAX is (intentionally?) left unspecified, according to
> commit 64dd117734d0 ("Unconditionally use MAX_EXPR/MIN_EXPR for MAX/MIN
The < and > operators separately already can cause exceptions, unless
you use -fno-trapping-math, in which case you cannot have LTGT at all.