On Tue, Jun 12, 2007 at 01:13:44PM -0700, Mark Glines wrote:
I just came up with an artificial benchmark and found that gcc-3.4.6
runs slightly faster with #pragma once protecting a header that includes
lots of other headers. (a chain of 200 other headers, in my test.) By
"slightly", I mean "compare a 0.86 second average to a 0.92 second
average, for 10 runs each".
For a more realistic benchmark, parrot r18883 compiles in 3m29.363s,
parrot r18884 compiles in 3m29.190s. So, for gcc-3.4.6 at least, I
think the difference might be lost in the noise.
Balancing the gain vs. loss: these small speed gains don't seem worth
losing the ability to compile on a tool chain that has worked fine until
this change. We can revisit that when/if the speed gain becomes more
significant, or MinGW gcc 3.4.5 switches over to 'current'.
Allison
