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* Re: optimization documentation
       [not found] <01E4A5BAEE42D411977100508BC22C9F05760CAA@tcexch3.taylorcor p.com>
@ 2003-10-29 18:03 ` Eljay Love-Jensen
  0 siblings, 0 replies; 2+ messages in thread
From: Eljay Love-Jensen @ 2003-10-29 18:03 UTC (permalink / raw)
  To: Van Eps, Nathan D. (James Tower), 'gcc-help@gcc.gnu.org'

Hi Nathan,

To figure out what the differences are between the various optimization settings, do this:

touch foo.cpp
g++ -O2 -save-temps -fverbose-asm -c foo.cpp
cat foo.s

Replace "-O2" with the one(s) that you are interested in.  Compare the differences in the .s files.  Make sure you save the foo.s that you are interested to compare against... :-)

Spiffy!  (This was previously posted on this forum; I did not figure it out on my own.)

HTH,
--Eljay


^ permalink raw reply	[flat|nested] 2+ messages in thread
* optimization documentation
@ 2003-10-29 17:50 Van Eps, Nathan D. (James Tower)
  0 siblings, 0 replies; 2+ messages in thread
From: Van Eps, Nathan D. (James Tower) @ 2003-10-29 17:50 UTC (permalink / raw)
  To: 'gcc-help@gcc.gnu.org'

Hello,

On the following documentation page, it says "-O also turns on
-fomit-frame-pointer on machines where doing so does not interfere with
debugging.". It also says "-O2 turns on all optimization flags specified by
-O.". Is "-fomit-frame-pointer" always turned on when you use "-O2", or does
the same condition of "-O" apply when you use "-O2"?

http://gcc.gnu.org/onlinedocs/gcc-3.3.2/gcc/Optimize-Options.html#Optimize%2
0Options

Thanks,
==============================
Nathan Van Eps

^ permalink raw reply	[flat|nested] 2+ messages in thread
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2003-10-29 18:03 ` optimization documentation Eljay Love-Jensen
2003-10-29 17:50 Van Eps, Nathan D. (James Tower)

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