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Re: Foating point: tracking change in between gcc 4.4.7 and gcc 4.9.2
- From: Andrew Haley <aph at redhat dot com>
- To: Mathieu Malaterre <mathieu dot malaterre at gmail dot com>
- Cc: gcc-help <gcc-help at gcc dot gnu dot org>
- Date: Thu, 10 Dec 2015 15:13:05 +0000
- Subject: Re: Foating point: tracking change in between gcc 4.4.7 and gcc 4.9.2
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On 12/10/2015 02:55 PM, Mathieu Malaterre wrote:
> Is there a way to test that for sure. A naive solution like:
>
> $ LD_PRELOAD=$HOME/libc.so.6 ./mycode
>
> results in
>
> relocation error: /home/mathieu/libc.so.6: symbol _dl_starting_up,
> version GLIBC_PRIVATE not defined in file ld-linux-x86-64.so.2 with
> link time reference
Sure. Find the different result and test it. All you have to do is
log all the calls to the standard functions and compare.
It's unlikely to be std::ceil or std::sqrt.
Andrew.