undefined reference" problem while compiling GHDL with GCC 4.6.3

HI All,
I am currently trying to Build GHDL-0.29 on top of a newer GCC 4.6.3(fedora 16),
../gcc-4.6.3/configure --enable-languages=vhdl --disable-bootstrap configured successfully. and applied Kevin Steffensen patch
(**broken link removed**) and then

'make CFLAGS="-O"' Got below error

collect2: ld returned 1 exit status
gnatlink: error when calling /usr/bin/gcc
gnatmake: *** link failed.
make[2]: *** [ghdl1] Error 4
make[2]: Leaving directory `/root/rpmbuild/BUILD/gcc-4.6.3-20120306/host-x86_64-unknown-linux-gnu/gcc'
make[1]: *** [all-gcc] Error 2
make[1]: Leaving directory `/root/rpmbuild/BUILD/gcc-4.6.3-20120306'
make: *** [all] Error 2

I found ghdl discussion https://www.mail-archive.com/debian-bugs-dist@lists.debian.org/msg61838.html for version dependencies, But I had all for fc 16 4.6.3 versions
gnat-
libc6
libgcc1
libgnat

Please give me suggestions to build new version of gcc

Regards
Raghavendra