Hi, r194664 in google/gcc-4_7 lost one line in libstdc++-v3/libsupc++/Makefile.am and did not regenerate Makefile.in (it seems to have been edited manually).
Now re-running automake in libstdc++ results in a non-trivial diff. The attached patch updates Makefile.am. With this patch the difference in generated files becomes trivial (line breaks only).
1.patch
Description: Binary data