krb5 commit: Make Emacs tags actually work

[Tom Yu]

https://github.com/krb5/krb5/commit/2a1d02f05ea734a5e7a81f69752a5d80b6598d48
commit 2a1d02f05ea734a5e7a81f69752a5d80b6598d48
Author: Tom Yu <tlyu at mit.edu>
Date:   Thu Jul 28 13:18:23 2016 -0400

    Make Emacs tags actually work

 .gitignore      |    3 +++
 src/Makefile.in |   12 ++++++++++++
 2 files changed, 15 insertions(+), 0 deletions(-)

diff --git a/.gitignore b/.gitignore
index 36117a2..3b63c98 100644
--- a/.gitignore
+++ b/.gitignore
@@ -129,6 +129,9 @@ local.properties
 /doc/html/
 /doc/pdf/
 
+# Emacs tags table
+/src/TAGS
+
 /src/config.log
 /src/config.status
 /src/configure
diff --git a/src/Makefile.in b/src/Makefile.in
index 4d8c6f1..d8c524f 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -667,3 +667,15 @@ check-copyright:
 	(cd $(top_srcdir) && \
 	$(FIND) . \( -name '*.[ch]' -o -name '*.hin' \) -print0 | \
 	$(XARGS) -0 python util/krb5-check-copyright.py)
+
+tags: FORCE
+	(cd $(top_srcdir) && \
+	$(FIND) . \( -name '*.[ch]' -o -name '*.hin' \) -print | \
+	etags --lang=c - && \
+	$(FIND) . -name '*.cpp' -print | etags --lang=c++ --append - && \
+	$(FIND) . -name '*.y' -print | etags --lang=yacc --append -)
+FORCE:
+.PHONY: FORCE tags
+
+distclean-unix:
+	$(RM) $(top_srcdir)/TAGS