From:	"Rafal 'Raf256' Maj" <rafal AT raf256 DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	-O3 doesnt remove dead code
Date:	14 Sep 2002 12:34:04 GMT
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To:	djgpp AT delorie DOT com
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Hello,
Following program compield with -03 does NOT had dead-code loop removed. 
This empty loop actualy IS executed (and program takes few seconds to 
complete)

int main() { for (long long int i=0; i<500000000; i++) ; return 0; } 

IMHO compiler at -O3 should optimize code to :

int main() { return 0; } 

why this dead-loop is not removed ?

-- 
Rafał 'Raf256' Maj
http://www.raf256.com

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