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-D_GLIBCXX_USE_CXX11_ABI=1 ineffective for devtoolset-7 on CentOS 7 [duplicate]

Recently, I noticed that my program has a big performance regression because the standard library implementation of gcc with version earlier than 5 makes list::size() an O(n).

I'm using CentOS 7.2 whose default gcc version is 4.8.5. So I installed scl and devtoolset-7, and rebuilt my program. However, I found that list::size() in my program is still an O(n) method, even if I explicitly make _GLIBCXX_USE_CXX11_ABI to 1.

Why? It's odd.

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user1559521 Avatar asked Dec 23 '17 09:12

user1559521


1 Answers

It is forcefully disabled in RHEL6/7.

https://bugzilla.redhat.com/show_bug.cgi?id=1546704

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xosp7tom Avatar answered Oct 18 '22 13:10

xosp7tom