[JSC] Work around GCC miscompilation in testmasm#1621
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magomez merged 1 commit intoWebPlatformForEmbedded:wpe-2.46from Feb 18, 2026
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https://bugs.webkit.org/show_bug.cgi?id=307056 Reviewed by Justin Michaud. It seems that GCC miscompiles the switch statement in testMoveConditionallyFloatingPointSameArg when -funswitch-loops is on (that's the case for -O3). The symptom is that we don't handle MacroAssembler::DoubleEqualAndOrdered (at least) and end up hitting the following RELEASE_ASSERT_NOT_REACHED();. Globally turn off this specific transformation when compiling with older versions of GCC, to avoid running into further hard-to-diagnose bugs. Canonical link: https://commits.webkit.org/307067@main
magomez
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Feb 18, 2026
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https://bugs.webkit.org/show_bug.cgi?id=307056
Reviewed by Justin Michaud.
It seems that GCC miscompiles the switch statement in testMoveConditionallyFloatingPointSameArg when -funswitch-loops is on (that's the case for -O3). The symptom is that we don't handle MacroAssembler::DoubleEqualAndOrdered (at least) and end up hitting the following RELEASE_ASSERT_NOT_REACHED();.
Globally turn off this specific transformation when compiling with older versions of GCC, to avoid running into further hard-to-diagnose bugs.
Canonical link: https://commits.webkit.org/307067@main
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