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From: "jonas.rahlf.basf at gmail dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug c++/101795] New: (x > QNaNf) is not a constant expression Date: Thu, 05 Aug 2021 22:08:16 +0000 [thread overview] Message-ID: <bug-101795-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101795 Bug ID: 101795 Summary: (x > QNaNf) is not a constant expression Product: gcc Version: 11.2.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: c++ Assignee: unassigned at gcc dot gnu.org Reporter: jonas.rahlf.basf at gmail dot com Target Milestone: --- Somehow (x > QNaNf) is not a constant expression, according to g++. I could not find anything in the c++ standard that would support this behaviour. Both clang and MSVC compile (x > QNaNf) as a constant expression. Interestingly, (x == QNaNf) seems to work fine with g++. Example: #include <limits> constexpr bool canCompile = std::numeric_limits<float>::quiet_NaN() > 1; Compiler output: error: '(+QNaNf > 1.0e+0f)' is not a constant expression See also: https://godbolt.org/z/vW651jPYh No extra compile options needed. I noticed this when attempting to compile std::lerp(a,b,NaN) (which is supposed to be constexpr) as a constant expression.
next reply other threads:[~2021-08-05 22:08 UTC|newest] Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top 2021-08-05 22:08 jonas.rahlf.basf at gmail dot com [this message] 2021-08-06 14:34 ` [Bug c++/101795] " glisse at gcc dot gnu.org 2022-12-25 7:21 ` pinskia at gcc dot gnu.org 2022-12-27 11:57 ` marxin at gcc dot gnu.org 2022-12-28 19:14 ` pinskia at gcc dot gnu.org
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