[Bug libstdc++/62313] Data race in debug iterators

["fdumont at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62313

--- Comment #4 from François Dumont <fdumont at gcc dot gnu.org> ---
For me there is no bug. Standard containers are known to not be thread safe. I
don't know what  Standard points are talking about it but what I consider as
valid was iterating through the container from different threads. However in
your case you are doing some iterator operations, no matter how simple they
are,  in one thread while modifying the container from another and this require
you to put some mutex in place to do so.

I think you will experiment the same issue with all versions of the Standard
lib, even the oldest ones. Synchronization of the list of iterators has never
been plan to cover this kind of usage which is considered as invalid.
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From: "jason at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/62302] [5 Regression] Change in the comdat used for constructors
Date: Sun, 31 Aug 2014 21:06:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?idb302

--- Comment #1 from Jason Merrill <jason at gcc dot gnu.org> ---
Author: jason
Date: Sun Aug 31 21:06:08 2014
New Revision: 214770

URL: https://gcc.gnu.org/viewcvs?rev!4770&root=gcc&view=rev
Log:
    PR c++/62302
    * optimize.c (cdtor_comdat_group): Just look at the
    DECL_ASSEMBLER_NAME of the 'tors.

Added:
    trunk/gcc/testsuite/g++.dg/abi/comdat1.C
Modified:
    trunk/gcc/cp/ChangeLog
    trunk/gcc/cp/optimize.c