Patchy's configure flags

[John Mandereau]

I wonder why Patchy has unconditionnally run configure with
--disable-optimising since last December or so.

I guess there used to be issues with optimisation for some GCC
versions. Could optimisations be enabled again now? Or better, could
we allow developers who run Patchy tune configure flags?

I'm asking this because I suspect the Pentium 4 at MSH Paris Nord
could build the docs significantly faster by building LilyPond with
appropriate GCC flags, instead of building a binary for a generic x86
processor.

John