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From: "michael at talamasca dot ocis.net" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c/52734] Incorrect optimization of uClibc sbrk()
Date: Tue, 27 Mar 2012 08:10:00 -0000
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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52734

--- Comment #6 from michael at talamasca dot ocis.net <michael at talamasca dot ocis.net> 2012-03-27 08:05:06 UTC ---
Created attachment 27011
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27011
Assembly output of Mikael's testcase, from Michael's computer

Here's the assembly output you requested.  The "-v" data is in the typescript
file added separately.

I've used the modified version of the case submitted by Mikael, rather than my
original file.

Notice that "bbb" appears in the assembly only twice.  The first time is the
increment in Mikael's aaa implementation, and the second is on a code path that
goes straight to the end of the function.  Nowhere in the code is the load of
ddd from bbb.