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RE: gcc compile-time performance

 > From: dewar at gnat dot com (Robert Dewar) 
 > Note that if you really intend to use -O0 to deliver, then the design
 > of gcc is quite unfortunate. The amount of code generated by gcc with
 > optimization off compares really poorly with other competing
 > compilers. It really is very cheap to do at least a little cleaning up
 > of code. To see in x86 code repeated cases of a variable being stored
 > and immediately loaded from the same location is sad.
 > We find almost none of our users delivering in -O0. If this is really
 > a pattern in other uses, then I think that's another reason for
 > looking at a -O0.5 which would try to do at least a little
 > optimziation. I am not even sure this would not speed things up, since
 > you would generate smaller assembler files.
 > (speed things up = speed up compilation)

I believe the idea of better -O0 is perhaps shared by others.  See:

for an example of doing smarter compilation at -O0 and getting smaller
code with a faster compile time.

Kaveh R. Ghazi			Director of Systems Architecture		Qwest Solutions

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