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Re: Faster compilation speed


On Friday, August 9, 2002, at 03:12 , Stan Shebs wrote:

Noel Yap wrote:

Build speeds are most helped by minimizing the number
of files opened and closed during the build.

Is this assertion based on empirical measurement, and if so, for what
source code and what system?  For instance, the longest source file
in GCC is about 15K lines, and at -O2, only a small percentage of
time is spent messing with files.  If I use -save-temps on cp/decl.c on
one of my (Linux) machines, I get a total time of about 38 sec from
source to asm.  If I just compile decl.i, it's about 37 sec, so that's
1 sec for *all* preprocessing, including all file opening/closing.
Since the preprocessor is integrated, I don't think you can separate
the timings in this way. :(  A 'gcc3 -E cp/decl.c -o decl.i' would
probably be more meaningful.

--Zem
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Ziemowit Laski                 1 Infinite Loop, MS 301-2K
Mac OS X Compiler Group        Cupertino, CA USA  95014-2083
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