kbuild: change kbuild to not rely on incorrect GNU make behavior

[mirror_ubuntu-artful-kernel.git] / Documentation / DocBook / Makefile

diff --git a/Documentation/DocBook/Makefile b/Documentation/DocBook/Makefile
index 1c955883cf58864015c7dd93243e819dd0b18429..2c6f66dea6500594b4e18764cdb88d3aee17cd31 100644 (file)
--- a/Documentation/DocBook/Makefile
+++ b/Documentation/DocBook/Makefile
@@ -28,7 +28,7 @@ PS_METHOD     = $(prefer-db2x)
 
 ###
 # The targets that may be used.
-.PHONY:        xmldocs sgmldocs psdocs pdfdocs htmldocs mandocs installmandocs
+PHONY += xmldocs sgmldocs psdocs pdfdocs htmldocs mandocs installmandocs
 
 BOOKS := $(addprefix $(obj)/,$(DOCBOOKS))
 xmldocs: $(BOOKS)
@@ -211,3 +211,9 @@ clean-dirs := $(patsubst %.xml,%,$(DOCBOOKS))
 
 #man put files in man subdir - traverse down
 subdir- := man/
+
+
+# Declare the contents of the .PHONY variable as phony.  We keep that
+# information in a variable se we can use it in if_changed and friends.
+
+.PHONY: $(PHONY)