Janne Grunau <[email protected]> writes:

> On 2012-01-31 11:40:11 -0500, Justin Ruggles wrote:
>> From: Reimar Döffinger <[email protected]>
>> 
>> The same as av_fast_malloc but uses av_mallocz and keeps extra
>> always-0 padding.
>> This does not mean the memory will be 0-initialized after each call,
>> but actually only after each growth of the buffer.
>> However this makes sure that
>> a) all data anywhere in the buffer is always initialized
>
> This feels too hacky and sounds if it's just used to silence "depends
> on uninitilized value" valgrind warnings.

Indeed, and this is the wrong way to "fix" such things.

[...]

>>  /**
>> + * Same behaviour av_fast_malloc but the buffer has additional
>> + * FF_INPUT_PADDING_SIZE at the end which will will always be 0.
>> + *
>> + * In addition the whole buffer will initially and after resizes
>
> also only after buffer growth
>
>> + * be 0-initialized so that no uninitialized data will ever appear.
>
> the old data which is preserved after a buffer shrink could be also
> considered uninitialized data.

Not only could, it should.

This patch should not be accepted without a better understanding of
what problem, if any, it is intended to solve.

-- 
Måns Rullgård
[email protected]
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