Options disabled under -Os

Options disabled under -Os

[Visda.Vokhshoori]

Hello,

In GCC documentation,  3.1 Options that Control Optimization: it is indicated -Os disables alignment of functions, jumps, labels, and loops.  However, with -v -Q passed to the compile step, I see all these options enabled under -Os.  Is this intended behavior, therefore a documentation bug?
I have tried this with GCC4.4.7 and GCC8.3.1

Thanks,
Visda

Re: Options disabled under -Os

[Kewen.Lin]

on 2019/12/19 上午12:49, Visda.Vokhshoori@microchip.com wrote:
> Hello,
> 
> In GCC documentation,  3.1 Options that Control Optimization: it is indicated -Os disables alignment of functions, jumps, labels, and loops.  However, with -v -Q passed to the compile step, I see all these options enabled under -Os.  Is this intended behavior, therefore a documentation bug?
> I have tried this with GCC4.4.7 and GCC8.3.1

Hi Visda,
This issue has been fixed in GCC 9 and trunk.
I can reproduce it with gcc 8.3.1 but it's gone with gcc 9.2.1 and latest trunk.

I also checked the latest gcc-branch-8 code, they are guarded in OPT_LEVELS_2_PLUS_SPEED_ONLY, so gcc8 just dumps inaccurate information but the behavior should be the same as documentation.


BR,
Kewen