Side effect of -finline-functions

[Jonathan Wakely]

On 3 May 2012 12:17, Mathieu Malaterre wrote:
> Hi all,
>
>  We are currently tracking an issue within the openjpeg codebase. One
> user reported that compilation with -O3 leads to incorrect result
> decompressing a particular image. He also noticed that compilation
> with -O2 -fgcse-after-reload  -fipa-cp-clone -fpredictive-commoning
> -ftree-vectorize -funswitch-loops does not produce any artefact.
> Therefore we concluded that the only possible side effect would be
> generated by the flag -finline-functions

The manual says "Not all optimizations are controlled directly by a
flag. Only optimizations that have a flag are listed in this section."
 So there may be additional optimisations at -O3 beyond those listed.

> Is there some kind of tools that could help us locate exactly which
> function is producing a different output with this flag ?

You could look at the various -fdump-tree options and compare the
output with and without that flag.