Wireshark-dev: Re: [Wireshark-dev] Optimizer options with autotools and CMake?
From: Evan Huus <eapache@xxxxxxxxx>
Date: Sun, 3 Aug 2014 14:15:32 -0400
On Sun, Aug 3, 2014 at 2:10 PM, Guy Harris <guy@xxxxxxxxxxxx> wrote:

On Aug 3, 2014, at 11:01 AM, Evan Huus <eapache@xxxxxxxxx> wrote:

> On Sun, Aug 3, 2014 at 1:40 PM, Guy Harris <guy@xxxxxxxxxxxx> wrote:
>> I've noticed, on occasion, that sometimes the CMake builds on the UN*X buildbots get warnings that the autotools builds don't.
>>
>> Recently, I tried to figure out what was different about the CMake builds; after some fixes that removed some incorrect differences between them, I eventually stumbled across the way to get CMake to produce makefiles that did verbose builds, printing the compile command as part of the build output, and found that the difference was very simple - autotools builds weren't building with a -O option, while CMake builds were building with -O2.
>
> I could have sworn my autotools builds used -O2... *goes to check*
>
> Yup, my master-1.12 vanilla autotools build adds -O2 to CFLAGS and CXXFLAGS. I don't have a master autotools build handy, but I can't recall any changes that would have affected that...

Autotools changing to default to -O2 in a version later than the version installed on the 32-bit OS X buildbot (which I think is running Snow Leopard, so the autotools version might be the one that shipped with Snow Leopard - that was before Apple stopped shipping autotools)?

Huh, like Jeff I didn't realize that was an autotools default - I thought we were already setting it ourselves.

+1 to explicitly specifying optimization flags on all build systems.