with gcc svn-trunk r206543 or later, gdc causes ICE when compiling libdruntime.

$ uname -a
Linux vmubuntu 3.8.0-35-generic #50~precise1-Ubuntu SMP Wed Dec 4 17:25:51 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

$ ../gcc/configure --prefix=/usr/local/gcc-head --enable-languages=c,d --enable-lto --disable-multilib --without-ppl --without-cloog-ppl --enable-checking=release --disable-nls --disable-bootstrapping
(snip)

$ make
(snip)
Making all in libdruntime
make[4]: Entering directory `/home/gccbuilder/build/x86_64-unknown-linux-gnu/libphobos/libdruntime'
/home/gccbuilder/build/./gcc/gdc -B/home/gccbuilder/build/./gcc/ -B/usr/local/gcc-head/x86_64-unknown-linux-gnu/bin/ -B/usr/local/gcc-head/x86_64-unknown-linux-gnu/lib/ -isystem /usr/local/gcc-head/x86_64-unknown-linux-gnu/include -isystem /usr/local/gcc-head/x86_64-unknown-linux-gnu/sys-include -o object_.o -Wall -g -frelease -O2 -nostdinc -pipe -Wno-deprecated -I ../../../../gcc/libphobos/libdruntime -I ./x86_64-unknown-linux-gnu -I .  -c ../../../../gcc/libphobos/libdruntime/object_.d
cc1d: internal compiler error: Segmentation fault
0x9500ff crash_signal
        ../../gcc/gcc/toplev.c:337
0x7fe99a build_type_inheritance_graph()
        ../../gcc/gcc/ipa-devirt.c:584
0x6e0305 analyze_functions
        ../../gcc/gcc/cgraphunit.c:953
0x6e1055 finalize_compilation_unit()
        ../../gcc/gcc/cgraphunit.c:2310
0x6580f4 d_finish_compilation(tree_node**, int)
        ../../gcc/gcc/d/d-objfile.cc:1957
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.
make[4]: *** [object_.o] Error 1
make[4]: *** [object_.o] Error 1
make[4]: Leaving directory `/home/gccbuilder/build/x86_64-unknown-linux-gnu/libphobos/libdruntime'
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory `/home/gccbuilder/build/x86_64-unknown-linux-gnu/libphobos'
make[2]: *** [all] Error 2
make[2]: Leaving directory `/home/gccbuilder/build/x86_64-unknown-linux-gnu/libphobos'
make[1]: *** [all-target-libphobos] Error 2
make[1]: Leaving directory `/home/gccbuilder/build'
make: *** [all] Error 2