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Bug 1190 - Clang/ARM falsely advertises __ARM_FEATURE_FMA regardless of its actual availability
Summary: Clang/ARM falsely advertises __ARM_FEATURE_FMA regardless of its actual avail...
Alias: None
Product: Eigen
Classification: Unclassified
Component: Core - vectorization (show other bugs)
Version: 3.3 (current stable)
Hardware: ARM - NEON Android
: Normal Unknown
Assignee: Nobody
Depends on:
Reported: 2016-04-04 20:34 UTC by Benoit Jacob
Modified: 2019-12-04 15:36 UTC (History)
4 users (show)


Description Benoit Jacob 2016-04-04 20:34:27 UTC
...and then generates slow emulation code as the instruction isn't available.

The only work-around for that is going to be to disable FMA on Clang/ARM.

Affected Clang versions: at least Clang 3.8.  (note though that 3.5 didn't seem to be affected).
Comment 2 Benoit Jacob 2016-04-05 14:08:22 UTC
Filed LLVM bug:
Comment 3 Nobody 2019-12-04 15:36:35 UTC
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