[FFmpeg-cvslog] r23119 - trunk/libavcodec/mpegaudiodec.c

[Alex Converse]

On Thu, May 13, 2010 at 2:06 PM, michael <subversion at mplayerhq.hu> wrote:
> Author: michael
> Date: Thu May 13 20:06:44 2010
> New Revision: 23119
>
> Log:
> 1.0 and the resulting exactly representable value must be marked as float as well,
> gcc is hopelessly trash.
>

"1.0" is a double even though it can fit in float.

The fact that after the division, the result can still fit exactly in
a float is a special case based on the form of the divisor.

The compiler can't do better here if the macro is used in further
arithmetic with doubles and with integers the situation is tenuous at
best.

There are plenty of places where gcc screws the pooch but this is one
optimization I would not have reasonable expectations for any good
compiler to make without sloppy math flags or
-fdowhatimeannotwhatisay.

Had you not exercised your prerogative to just commit this all at
once, you could have gotten some review from those of us who regularly
write floating point code.

</flame>