/usr/src/gcc-4.7/debian/patches/ibm-branch.diff is in gcc-4.7-source 4.7.3-12ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 | # DP: updates from the ibm/4.7 branch upto 2012xxxx (r175989).
svn diff svn://gcc.gnu.org/svn/gcc/branches/gcc-4_7-branch@175885 svn://gcc.gnu.org/svn/gcc/branches/ibm/gcc-4_6-branch \
| sed -r 's,^--- (\S+)\t(\S+)(.*)$,--- a/src/\1\t\2,;s,^\+\+\+ (\S+)\t(\S+)(.*)$,+++ b/src/\1\t\2,' \
| awk '/^Index:.*\.(class|texi)/ {skip=1; next} /^Index:/ { skip=0 } skip==0'
|