IO speed slipping again?

[Benjamin Kosnik]

>In my case, it turns out that the library was not being built with
>optimization on.  When I set it to -O2, the times went back down
>again.  I still don't know why it's not using optimization in the
>builds, though.

(What is CXXFLAGS set to?)

Did you try making a performance baseline with 

cd (build)/libstdc++-v3
make check
cd testsuite
make check-peformance?

Try it, and let me know what you think.

I've started archiving this so that I can have a better idea about what
changes are doing.

-benjamin