Merge branch 'bc/maint-diff-hunk-header-fix' into maint

* bc/maint-diff-hunk-header-fix: t4018-diff-funcname: test syntax of builtin xfuncname patterns diff hunk pattern: fix misconverted "\{" tex macro introducers diff: use extended regexp to find hunk headers diff.*.xfuncname which uses "extended" regex's for hunk header selection diff.c: associate a flag with each pattern and use it for compiling regex diff.c: return pattern entry pointer rather than just the hunk header pattern Conflicts: Documentation/gitattributes.txt