Build Fedora Core 6 gcc from src rpm on Fedora Core 9 with original options

[Mark Ryden]

Hello,

I am trying to install and build gcc from src rpm.
I am installing it on Fedora Core 9, and I downloaded the gcc src rpm
of Fedora Core 6.
I want the default gcc to stay as it is (of Fedora Core 9); and that
side by side with it, there will be
gcc of Fedora Core 6, in a different path.

So , this is what I did:

gcc src.rpm and ran:
rpm -ivh
and then
rpmbuild -bp --target=x86_64 gcc41.spec (there are many pathces in
this source rpm)

Now, under /usr/src/redhat/BUILD I have a folder named:
gcc-4.1.1-20061011

I navigated there; I should run ./configure, but is there a way I can
know what are the options
for the configure which the gcc on FC6 was compiled with ?  There are
really many options and
I am afraid that if I will miss one, the when trying to build a
module /kernel/some other projects with the generated gcc, it will give
errors. (I have access to a machine on which FC6 with this gcc runs;
but is there a way I can know what
are the options gcc was compiled when this gcc rpm was build ? maybe
by some option to
rpmbuild --rebuild??)

Any help will be appreciated.

Regards,
Mark