.gitattributes: set file type for C files

Set the diff attribute for C source file to "cpp" in order to improve
git's ability to determine hunk headers.  In particular it helps avoid
showing unindented labels in hunk headers.  That in turn is useful for
git diff -W and git grep -W, which show whole functions now instead of
stopping at a label.

Signed-off-by: Rene Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/.gitattributes b/.gitattributes
index 5e98806c6c..320e33c327 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,3 +1,3 @@
 * whitespace=!indent,trail,space
-*.[ch] whitespace=indent,trail,space
+*.[ch] whitespace=indent,trail,space diff=cpp
 *.sh whitespace=indent,trail,space