genus2reduction version 0.3-2 failed to build on amd64 with GCC-4.6/oneiric

genus2reduction version 0.3-2 failed to build on amd64 with GCC-4.6/oneiric
Link to failed build: https://launchpad.net/ubuntu/+archive/test-rebuild-20110413/+buildjob/2450867

Details about the rebuild:
https://lists.ubuntu.com/archives/ubuntu-devel/2011-April/033042.html

Direct link to the build log: https://launchpad.net/ubuntu/+archive/test-rebuild-20110413/+buildjob/2450867/+files/buildlog_ubuntu-natty-amd64.genus2reduction_0.3-2_FAILEDTOBUILD.txt.gz

This log snippet might be of interest, since it triggered the matcher 'Purging chroot-autobuild'.
Excerpt 2001 lines into the build log:

/build/buildd/genus2reduction-0.3/genus2reduction.c:658: undefined reference to `gdiv'
/build/buildd/genus2reduction-0.3/genus2reduction.c:476: undefined reference to `pol_1'
/build/buildd/genus2reduction-0.3/genus2reduction.c:487: undefined reference to `truecoeff'
/build/buildd/genus2reduction-0.3/genus2reduction.c:487: undefined reference to `truecoeff'
/build/buildd/genus2reduction-0.3/genus2reduction.c:488: undefined reference to `truecoeff'
/build/buildd/genus2reduction-0.3/genus2reduction.c:489: undefined reference to `gmul'
/build/buildd/genus2reduction-0.3/genus2reduction.c:489: undefined reference to `gmul2n'
/build/buildd/genus2reduction-0.3/genus2reduction.c:489: undefined reference to `gsqr'
/build/buildd/genus2reduction-0.3/genus2reduction.c:489: undefined reference to `gsub'
/build/buildd/genus2reduction-0.3/genus2reduction.c:481: undefined reference to `gmul'
collect2: ld returned 1 exit status
make[1]: *** [genus2reduction] Error 1
make[1]: Leaving directory `/build/buildd/genus2reduction-0.3'
make: *** [debian/stamp-makefile-build] Error 2
dpkg-buildpackage: error: debian/rules build gave error exit status 2
******************************************************************************
Build finished at 20110422-2122
FAILED [dpkg-buildpackage died]
Purging chroot-autobuild/build/buildd/genus2reduction-0.3