bug#19997: Performance differences between Git sources and release tarballs?

[Paul Eggert]

sur-behoffski wrote:
> Looking at Grep's "configure --help" output, I see that
> "--enable-gcc-warnings" is an option, and, with some experimentation with
> invoking compilation in different environments, it seems that a slew of
> warning options is enabled in the development tree, that are not enabled in
> the release tarball.

These shouldn't affect grep's runtime performance.

I don't know why you're observing the performance you do.  It could be that 
you're building 'grep' differently from the way Gentoo builds it.  You might try 
building both grep 2.21 and grep master yourself, with the same build procedure 
both ways.