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

diff --cc Documentation/gitattributes.txt
index 89627688b81761771f17865a67d10ad85a830ea2,9259637609da2b34d15d217daeebeccc6ba853e4..53da9b4f6ba34b03768d77158c19d53e44681809
--- 1/Documentation/gitattributes.txt
--- 2/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@@ -288,9 -288,9 +288,9 @@@ for paths
  *.tex diff=tex
  ------------------------
  
- Then, you would define a "diff.tex.funcname" configuration to
 -Then, you would define "diff.tex.xfuncname" configuration to
++Then, you would define a "diff.tex.xfuncname" configuration to
  specify a regular expression that matches a line that you would
 -want to appear as the hunk header, like this:
 +want to appear as the hunk header "TEXT", like this:
  
  ------------------------
  [diff "tex"]

diff --cc diff.c
Simple merge