Work-around for GNU GLOBAL on 64-bit Ubuntu.

Makefile

Index: Makefile
diff --git a/Makefile b/Makefile
index 16d8ef2d4506b984ecd6f901e65cfce40d38b421..93746a8827163ef66f56efe9b241dd8a86903198 100644
--- a/Makefile
+++ b/Makefile
@@ -471,11 +471,13 @@ grokdump: ia32.release
 gtags.files: $(GYPFILES) $(ENVFILE)
 	@find include src test -name '*.h' -o -name '*.cc' -o -name '*.c' > $@
 
-GTAGS GRTAGS GPATH: gtags.files
-	@GTAGSFORCECPP=yes gtags -i -q
+# We need to manually set the stack limit here, to work around bugs in
+# gmake-3.81 and global-5.7.1 on recent 64-bit Linux systems.
+GPATH GRTAGS GSYMS GTAGS: gtags.files
+	@bash -c 'ulimit -s 10240 && GTAGSFORCECPP=yes gtags -i -q -f $<'
 
 gtags.clean:
-	rm -f GTAGS GRTAGS GPATH gtags.files
+	rm -f gtags.files GPATH GRTAGS GSYMS GTAGS
 
 # Dependencies.
 # Remember to keep these in sync with the DEPS file.