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* [Bug middle-end/78249] In consistent results for 0.0 * inf when optimizer is enabled
[not found] <bug-78249-4@http.gcc.gnu.org/bugzilla/>
@ 2022-03-12 15:22 ` roger at nextmovesoftware dot com
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From: roger at nextmovesoftware dot com @ 2022-03-12 15:22 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78249
Roger Sayle <roger at nextmovesoftware dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |roger at nextmovesoftware dot com
Status|NEW |RESOLVED
Resolution|--- |DUPLICATE
--- Comment #4 from Roger Sayle <roger at nextmovesoftware dot com> ---
After a little investigating it turns out that this is a duplicate of PR
middle-end/51446. When multiplying 0 * Inf, x86/ia64 chips return -NaN, where
other architectures return NaN. Alas IEEE doesn't specify the sign of the NaN,
so GCC isn't "wrong", but it's odd that multiplications performed at run-time
produce
a different result to those computed at compile-time (hence the -O0 vs -O1/2/3
differences). Ideally this should (perhaps) be controlled by a target hook.
*** This bug has been marked as a duplicate of bug 51446 ***
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[not found] <bug-78249-4@http.gcc.gnu.org/bugzilla/>
2022-03-12 15:22 ` [Bug middle-end/78249] In consistent results for 0.0 * inf when optimizer is enabled roger at nextmovesoftware dot com
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