Getting data from a nested configure script?

[Benoit Sigoure]

Howdy,
it's been a while :-)

Say that I use AC_CONFIG_SUBDIRS([foo]), is there a standard way for
the parent configure to retrieve some information from foo's
configure?  For instance foo's configure may compute a set of compiler
flags and I want these flags to be passed up to the top-level
configure for some reason (and I'm trying to avoid duplicating the
entire check in the top-level configure -- moreover foo may also be a
3rd party package which I don't control although it's not the case in
my specific setup).

Thanks!

-- 
Benoit Sigoure aka Tsuna
EPITA Research and Development Laboratory
Software Engineer @ Google