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Subject: [Bug target/54888] GCC with -Os is faster than -O3 on some AVR code
Date: Mon, 22 Oct 2012 12:41:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54888

--- Comment #3 from mojo at world3 dot net 2012-10-22 12:40:57 UTC ---
(In reply to comment #2)

> And I actually don't understand teh issue: Optimizing for size does not require
> to produce slow code.  The code may run fast.

-O3 is supposed to produce the fastest possible code, but it doesn't. -Os is
faster. At the very least the two should be equal.

In other words -O3 is broken.