From: Florian Weimer <fw@deneb.enyo.de>
To: Nikolaus Dunn <nikdunn1979@gmail.com>
Cc: Jonathan Wakely <jwakely.gcc@gmail.com>,
gcc-help <gcc-help@gcc.gnu.org>
Subject: Re: Optimization question
Date: Tue, 27 Sep 2016 18:32:00 -0000 [thread overview]
Message-ID: <87zimtxkg6.fsf@mid.deneb.enyo.de> (raw)
In-Reply-To: <4e4b52d1-d9fd-ef2b-6e53-99f4b68a9c4b@gmail.com> (Nikolaus Dunn's message of "Tue, 27 Sep 2016 13:39:01 -0400")
* Nikolaus Dunn:
> std::ostringstream however does not call my new OR delete with no
> optimization. With -O2, it calls only my delete.
>
> If I do not attempt to wrap malloc and free, I get the same
> result. std::vector calls my new and delete, ostringstream calls
> neither.
>
> The command line I used to compile it is:
> g++ -g -O2 --std=c++14 -Wl,-wrap,malloc -Wl,-wrap,free Test.c -o test.exe
“-Wl,-wrap,malloc -Wl,-wrap,free” is only effective for newly-compiled
code. Your example probably uses some template instantiations which
are supplied by libstdc++, and these will keep calling the unwrapped
malloc/free implementations.
I don't know if there are mechanisms on mingw which are comparable to
ELF symbol interposition.
next prev parent reply other threads:[~2016-09-27 18:32 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <c8204c33-7085-5dde-96f3-92d7745a0018@gmail.com>
2016-09-27 15:20 ` Florian Weimer
2016-09-27 17:10 ` Jonathan Wakely
2016-09-27 17:39 ` Nikolaus Dunn
2016-09-27 17:49 ` Jonathan Wakely
2016-09-27 18:32 ` Florian Weimer [this message]
2016-09-28 10:13 ` Jonathan Wakely
2000-01-07 11:39 optimization question Igor Schein
2000-04-01 0:00 ` Igor Schein
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