/usr/src/gcc-6/debian/patches/svn-doc-updates.diff is in gcc-6-source 6.4.0-17ubuntu1.
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1 2 3 4 5 | # DP: updates from the 6 branch upto 20170406 (documentation).
svn diff svn://gcc.gnu.org/svn/gcc/tags/gcc_6_4_0_release svn://gcc.gnu.org/svn/gcc/branches/gcc-6-branch \
| sed -r 's,^--- (\S+)\t(\S+)(.*)$,--- a/src/\1\t\2,;s,^\+\+\+ (\S+)\t(\S+)(.*)$,+++ b/src/\1\t\2,' \
| awk '/^Index:.*\.texi/ {skip=0; print; next} /^Index:/ {skip=1; next} skip==0'
|