mg version 20110120-1 failed to build in oneiric

mg version 20110120-1 failed to build in oneiric
Link to failed build: https://launchpad.net/ubuntu/+archive/test-rebuild-20110816/+build/2705086

Details about the rebuild:
http://people.ubuntuwire.org/~wgrant/rebuild-ftbfs-test/test-rebuild-20110816-oneiric.html

Direct link to the build log: https://launchpad.net/ubuntu/+archive/test-rebuild-20110816/+build/2705086/+files/buildlog_ubuntu-oneiric-amd64.mg_20110120-1_FAILEDTOBUILD.txt.gz

This log snippet might be of interest, since it triggered the matcher 'Purging chroot-autobuild'.
Excerpt 256 lines into the build log:

gcc -g -O2 -g -Wall -Werror -Wno-strict-aliasing -c cinfo.c
gcc -g -O2 -g -Wall -Werror -Wno-strict-aliasing -c cmode.c
cmode.c: In function 'cc_indent':
cmode.c:161:10: error: variable 'dci' set but not used [-Werror=unused-but-set-variable]
cmode.c: In function 'getindent':
cmode.c:229:6: error: variable 'contp' set but not used [-Werror=unused-but-set-variable]
cmode.c:220:6: error: variable 'ccol' set but not used [-Werror=unused-but-set-variable]
cc1: all warnings being treated as errors

make[1]: *** [cmode.o] Error 1
make[1]: *** Waiting for unfinished jobs....
make[1]: Leaving directory `/build/buildd/mg-20110120'
dh_auto_build: make -j2 returned exit code 2
make: *** [build] Error 2
dpkg-buildpackage: error: debian/rules build gave error exit status 2
******************************************************************************
Build finished at 20110822-0416
FAILED [dpkg-buildpackage died]
Purging chroot-autobuild/build/buildd/mg-20110120