Prevent compilers from using FMA instructions#1033
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langou merged 2 commits intoReference-LAPACK:masterfrom Jul 13, 2024
Merged
Prevent compilers from using FMA instructions#1033langou merged 2 commits intoReference-LAPACK:masterfrom
langou merged 2 commits intoReference-LAPACK:masterfrom
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…FMAs where the different rounding can lead to a change in control flow.
langou
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Jul 12, 2024
This was referenced Jan 21, 2026
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Fixes #1031
Description
As described in #1031 when the compiler uses FMA instructions, errors in
?GEEVXcan increase up toSQRT(EPS). The different rounding of the FMA instructions causes a change in control flow, which produces the errors. This MR uses explicit parentheses to prevent the compiler from using FMA instructions for those results, which are compared against zero in subsequent if-statements.Checklist