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Bug#635899: Update



The option text has now also been changed to "If unsure, say N"[1]
with the following rationale:

| Sadly, -Os keeps on generating some very suboptimal code for certain
| cases, to the point where any I$ miss upside is swamped by the downside.
| The main ones are:
|
|  - using "rep movsb" for memcpy, even on CPU's where that is
|    horrendously bad for performance.
|
|  - not honoring branch prediction information, so any I$ footprint you
|    win from smaller code, you lose from less code density in the I$.
|
|  - using divide instructions when that is very expensive.

[1]: http://git.kernel.org/linus/3a55fb0d9fe8e2f4594329edd58c5fd6f35a99dd

-- 
Romain Francoise <rfrancoise@debian.org>
http://people.debian.org/~rfrancoise/


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