I've read that NPTL is not active for systems above i686.
I've a P4 2.4 hyperthreaded (I need it for my project).
I've the headers for nptl but when i type a libc.so.X it shows me that linuxthread are enable.
Is there a way to use nptl. I think i have to build glibc with an option...(i've read somewhere --enable-add-on=nptl). Is there another way than rebuild.
And if i have to build glibc, how it works :
* do i have to build the kernel ? before/after build glibc
* do i have to build gcc ?

And finally,
what kind of incompatibility i risk ?