[PATCH v2] Makefile: add target for gtags

[Steffen Trumtrar]

The scripts/tags.sh file already supports the generation of gtags with
GNU GLOBAL. The only thing missing is the makefile target to use it.

Copy the setup from the Linux Kernel to allow usage of gtags with barebox.

Signed-off-by: Steffen Trumtrar <s.trumtrar at pengutronix.de>
---
 .gitignore |    6 ++++++
 Makefile   |    7 ++++---
 2 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/.gitignore b/.gitignore
index 1dec248..710bce0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -70,6 +70,12 @@ series
 # cscope files
 cscope.*
 
+# gnu global files
+GPATH
+GRTAGS
+GSYMS
+GTAGS
+
 # patches
 *.patch
 scripts/gen_netx_image
diff --git a/Makefile b/Makefile
index 640e589..502e009 100644
--- a/Makefile
+++ b/Makefile
@@ -353,7 +353,7 @@ endif
 # of make so .config is not included in this case either (for *config).
 
 no-dot-config-targets := clean mrproper distclean \
-			 cscope TAGS tags help %docs check% \
+			 cscope gtags TAGS tags help %docs check% \
 			 include/generated/version.h headers_% \
 			 kernelrelease kernelversion
 
@@ -986,7 +986,7 @@ MRPROPER_DIRS  += include/config include2 usr/include
 MRPROPER_FILES += .config .config.old include/asm .version .old_version \
                   include/generated/autoconf.h include/generated/version.h      \
                   include/generated/utsrelease.h include/config.h           \
-		  Module.symvers tags TAGS cscope*
+		  Module.symvers tags TAGS cscope* GPATH GTAGS GRTAGS GSYMS
 
 # clean - Delete most, but leave enough to build external modules
 #
@@ -1072,6 +1072,7 @@ help:
 	@echo  '  dir/file.ko     - Build module including final link'
 	@echo  '  tags/TAGS	  - Generate tags file for editors'
 	@echo  '  cscope	  - Generate cscope index'
+	@echo  '  gtags	  	  - Generate GNU GLOBAL index'
 	@echo  '                    (default: $(INSTALL_HDR_PATH))'
 	@echo  ''
 	@echo  'Static analysers'
@@ -1114,7 +1115,7 @@ htmldocs: Doxyfile.version
 quiet_cmd_tags = GEN     $@
       cmd_tags = $(CONFIG_SHELL) $(srctree)/scripts/tags.sh $@
 
-tags TAGS cscope: FORCE
+tags TAGS cscope gtags: FORCE
 	$(call cmd,tags)
 
 
-- 
1.7.10.4