alsa-lib TLVs and valgrind

alsa-lib TLVs and valgrind

[Sebastian H.]

Hello list

I'm about to release a new version of alsamixer-qt4
(now named qasmixer) and ran the program through valgrind.

valgrind --track-origins=yes src/qasmixer &> valgrind.log


The log file contains tons of warnings like this

==3432== Conditional jump or move depends on uninitialised value(s)
...
... (qasmixer function calls)
...
==3432==  Uninitialised value was created by a heap allocation
... malloc (vg_replace_malloc.c:236)
... init_db_range (simple_none.c:1111)
... get_dB_range (simple_none.c:1156)
... get_dB_range_ops (simple_none.c:1173)
... snd_mixer_selem_get_playback_dB_range (simple.c:298)
...
... (qasmixer function calls)
...

The fresh alsa-lib-10-24.1 was used for this, compiled with debug
symbols enabled. Drivers are from Debian/squeeze.

This issue doesn't seem critical for the application but it totally
floods the valgrind.log file.

Best,
Sebastian Holtermann

Re: alsa-lib TLVs and valgrind

[Clemens Ladisch]

Sebastian H. wrote:
> I'm about to release a new version of alsamixer-qt4
> (now named qasmixer) and ran the program through valgrind.
> 
> valgrind --track-origins=yes src/qasmixer &> valgrind.log
> 
> The log file contains tons of warnings like this
> 
> ==3432== Conditional jump or move depends on uninitialised value(s)
> ...
> ... (qasmixer function calls)
> ...
> ==3432==  Uninitialised value was created by a heap allocation
> ... malloc (vg_replace_malloc.c:236)
> ... init_db_range (simple_none.c:1111)
> ... get_dB_range (simple_none.c:1156)
> ... get_dB_range_ops (simple_none.c:1173)
> ... snd_mixer_selem_get_playback_dB_range (simple.c:298)

Valgrind doesn't know about some of the ALSA ioctls.
Somebody would have to add them to valgrind.


Regards,
Clemens

Re: alsa-lib TLVs and valgrind

[Sebastian H.]

Am 02.02.2011 14:12, schrieb Clemens Ladisch:
> Sebastian H. wrote:
>> I'm about to release a new version of alsamixer-qt4
>> (now named qasmixer) and ran the program through valgrind.
>>
>> valgrind --track-origins=yes src/qasmixer &> valgrind.log
>>
>> The log file contains tons of warnings like this
>>
>> ==3432== Conditional jump or move depends on uninitialised value(s)
>> ...
>> ... (qasmixer function calls)
>> ...
>> ==3432==  Uninitialised value was created by a heap allocation
>> ... malloc (vg_replace_malloc.c:236)
>> ... init_db_range (simple_none.c:1111)
>> ... get_dB_range (simple_none.c:1156)
>> ... get_dB_range_ops (simple_none.c:1173)
>> ... snd_mixer_selem_get_playback_dB_range (simple.c:298)
> 
> Valgrind doesn't know about some of the ALSA ioctls.
> Somebody would have to add them to valgrind.

That seems to require quite some effort - also to maintain.
Couldn't just the dB min/max values be initialized with 0 or sth.?

Sebastian

Re: alsa-lib TLVs and valgrind

[Clemens Ladisch]

Sebastian H. wrote:
> Am 02.02.2011 14:12, schrieb Clemens Ladisch:
> > Valgrind doesn't know about some of the ALSA ioctls.
> > Somebody would have to add them to valgrind.
> 
> That seems to require quite some effort - also to maintain.
> Couldn't just the dB min/max values be initialized with 0 or sth.?

Then it wouldn't be possible for valgrind to catch wrong uses of the
ioctl.


Regards,
Clemens

Re: alsa-lib TLVs and valgrind

[Sebastian H.]

Am 02.02.2011 16:12, schrieb Clemens Ladisch:
> Sebastian H. wrote:
>> Am 02.02.2011 14:12, schrieb Clemens Ladisch:
>>> Valgrind doesn't know about some of the ALSA ioctls.
>>> Somebody would have to add them to valgrind.
>>
>> That seems to require quite some effort - also to maintain.
>> Couldn't just the dB min/max values be initialized with 0 or sth.?
> 
> Then it wouldn't be possible for valgrind to catch wrong uses of the
> ioctl.

Ok. My knowledge of how valgrind works is limited anyway.

Thank you,
Sebastian