I see the same issue and have an easy reproducer. Downgrade to libgmp10 from wheezy fixes it.
$ cat reproducer.c void stupid() { int i; unsigned int val = 0; for (i = 0; i < 1; i++) { val *= 1; } } $ /usr/lib/gcc/x86_64-linux-gnu/4.6/cc1 -quiet -imultilib . -imultiarch x86_64-linux-gnu reproducer.c -quiet -dumpbase reproducer.c -mtune=generic -march=x86-64 -auxbase reproducer -O2 -o /tmp/xxreproducer.c: In function âstupidâ: reproducer.c:8:1: internal compiler error: Aborted Please submit a full bug report, with preprocessed source if appropriate. See <file:///usr/share/doc/gcc-4.6/README.Bugs> for instructions. $ dpkg --list libgmp10 Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) ||/ Name Version Description +++-==============-==============-============================================ ii libgmp10:amd64 2:5.0.5+dfsg-1 Multiprecision arithmetic library $ sudo apt-get install libgmp10=2:5.0.4+dfsg-1 Reading package lists... Done Building dependency tree Reading state information... Done The following packages will be DOWNGRADED: libgmp10 0 upgraded, 0 newly installed, 1 downgraded, 0 to remove and 0 not upgraded. Need to get 248 kB of archives. After this operation, 48.1 kB disk space will be freed. Do you want to continue [Y/n]? Get:1 http://debian.debian.zugschlus.de/debian/ wheezy/main libgmp10 amd64 2:5.0.4+dfsg-1 [248 kB] Fetched 248 kB in 0s (552 kB/s) debconf: delaying package configuration, since apt-utils is not installed dpkg: warning: downgrading libgmp10:amd64 from 2:5.0.5+dfsg-1 to 2:5.0.4+dfsg-1. (Reading database ... 15258 files and directories currently installed.) Preparing to replace libgmp10:amd64 2:5.0.5+dfsg-1 (using .../libgmp10_2%3a5.0.4+dfsg-1_amd64.deb) ... Unpacking replacement libgmp10:amd64 ... Setting up libgmp10:amd64 (2:5.0.4+dfsg-1) ... $ /usr/lib/gcc/x86_64-linux-gnu/4.6/cc1 -quiet -imultilib . -imultiarch x86_64-linux-gnu reproducer.c -quiet -dumpbase reproducer.c -mtune=generic -march=x86-64 -auxbase reproducer -O2 -o /tmp/xx $ -- To UNSUBSCRIBE, email to debian-bugs-rc-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org