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From: "luto at kernel dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/55522] -funsafe-math-optimizations is unexpectedly
 harmful, especially w/ -shared
Date: Thu, 08 Sep 2022 17:09:29 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D55522

--- Comment #16 from Andy Lutomirski <luto at kernel dot org> ---
(In reply to Andrew Pinski from comment #13)
> Patient: Doctor it hurts when I do this.
> Doctor: then don't do that and if you read the instructions I gave you I
> told you I would hurt this way.

I think this analogy is off.  Maybe for most questionable optimization or
codegen options it would apply, but -ffast-math is more like:

Patient: Doctor, it hurts me when my neighbor does this.
Doctor: Then tell your neighbor not to read that and to read the fine print=
 on
the box.

If nitroglycerin pills have side effects and patients need to read the labe=
l,
maybe fine.  But if they start exploding and breaking other peoples' window=
s,
that's a whole different problem.=