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> Gcc -o4 Flag, Is it different than -O3
ShiroiKuma
post Mar 27 2007, 10:04 AM
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I'm playing around with optimizing compiled packages to run fine on Ångström, but the question isn't really Ångström-specific.

I've seen on Meanie's blog on building Firefox natively that he used the -O4 option in CFLAGS.

I've looked but not found anything substantive on this flag. One Finnish page on the web states that if -On has n higher than 3, then the flag is automatically interpreted as -O3. Is this so? Or is there a difference between these?
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speculatrix
post Mar 28 2007, 02:17 AM
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If you haven't seen the film "Spinal Tap", the joke won't make any sense.
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ShiroiKuma
post Mar 28 2007, 04:58 AM
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QUOTE(speculatrix @ Mar 28 2007, 11:17 AM)
If you haven't seen the film "Spinal Tap", the joke won't make any sense.
*

smile.gif Didn't get the joke either...

How about the original issue though, is there really an -O4 flag that furthers optimization, or is it just the same as -O3?
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koen
post Mar 28 2007, 05:00 AM
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QUOTE(ShiroiKuma @ Mar 28 2007, 12:58 PM)
QUOTE(speculatrix @ Mar 28 2007, 11:17 AM)
If you haven't seen the film "Spinal Tap", the joke won't make any sense.
*

smile.gif Didn't get the joke either...

How about the original issue though, is there really an -O4 flag that furthers optimization, or is it just the same as -O3?
*



Just keep in mind that you're reading from *slow* media into a tiny amount of RAM, so 'optimized' binaries will execute slower in the end. I heard the people at nokia use -Os for certain applications because execution time is IO-limited.
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