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From: "amker at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c++/95638] [10/11 Regression] Legit-looking code doesn't work
 with -O2
Date: Sun, 14 Jun 2020 00:47:08 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D95638

--- Comment #6 from bin cheng <amker at gcc dot gnu.org> ---
We call graphds_scc twice to break alias dependence, with alias dependence
edges skipped in the second call.  The code (both before and after
r10-7184-ge4e9a59105a81cdd6c1328b0a5ed9fe4cc82840e) tries to rectify post o=
rder
information after the second call, however it never gets it right.  Actuall=
y I
don't think it can be easily rectified (if possible).

Will test another patch which records/restores post order information for t=
he
second call.=