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Re: long double test failures due to underflow exception getting set?
- From: Wilco Dijkstra <Wilco dot Dijkstra at arm dot com>
- To: "Ellcey, Steve" <Steve dot Ellcey at cavium dot com>, Carlos O'Donell <carlos at redhat dot com>
- Cc: "libc-alpha at sourceware dot org" <libc-alpha at sourceware dot org>, nd <nd at arm dot com>
- Date: Thu, 20 Jul 2017 17:32:29 +0000
- Subject: Re: long double test failures due to underflow exception getting set?
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Carlos wrote:
> Neither DJ nor Szabolcs's glibc 2.26 builds showed those failures:
Actually Szabolcs mentioned trunk GCC has some issues with long double.
I don't know the details but I imagine GCC lifts some FP operations across
fegetenv/fesetenv calls (or similar) which may be a bug depending on the
optimization setting (I guess you need -ftrapping-math to block such lifting).
Wilco