[LAU] [Jack-Devel] jack2 turned verbose

David Adler david.jo.adler at gmail.com
Fri Jun 1 16:49:02 UTC 2012


On Fri, Jun 1, 2012 at 4:21 PM, Nedko Arnaudov wrote:
> David Adler writes:
>> On Fri, Jun 1, 2012 at 2:52 PM, Robin Gareus wrote:
>>>
>>> It might have to do with Arch's compiler[-flags] and how jack2 uses
>>> unions .. or scoping: JackGlobals vs Engine-Parameters.. although I
>>> don't have an explanation.. all seems good.
>>
>> Compiler flags (for 32bit) are, (from unaltered /etc/makepkg.conf):
>> CXXFLAGS="-march=i686 -mtune=generic -O2 -pipe -fstack-protector
>> --param=ssp-buffer-size=4 -D_FORTIFY_SOURCE=2"
>
> Don't use -O2 nor -O1, use -O0
>
> I'm aware of at least one *compiler* bug that causes jackdbus to
> misbehave. Yes, i analyzed the generated assembly. Affected are both
> i32 and amd64 targets. Atm the only reports are from Arch users. The bad
> machine code is created for th control api implementation, in parts that
> use unions (jack parameter values).

Symptoms disappear when using -fpermissive and/or -O0 (instead of -O2),
with no changes in the source files.

So is this then an upstream or a downstream issue?

Nedko, does your advice to use -O0 only concern Jack or everything?
I'm compiling lots of software here, usually -O2 usually doesn't seem
to cause problems.


best,
david


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