From bc96c4518e4430f0cd996b2c77fe8e08d7694efa Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <eelco.dolstra@logicblox.com>
Date: Fri, 22 Nov 2013 15:10:33 +0000
Subject: [PATCH] Automatically emit make rules for header files

---
 .gitignore   |  1 +
 Makefile.lib | 10 ++++++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/.gitignore b/.gitignore
index a8f5a23791..ed9bd45a45 100644
--- a/.gitignore
+++ b/.gitignore
@@ -129,6 +129,7 @@ Makefile.config
 *.la
 *.o
 *.so
+*.dep
 *~
 
 # GNU Global
diff --git a/Makefile.lib b/Makefile.lib
index d681cf7412..1aec37c76f 100644
--- a/Makefile.lib
+++ b/Makefile.lib
@@ -7,10 +7,10 @@ LIBS =
 QUIET = @
 
 %.o: %.cc
-	$(QUIET) g++ -o $@ -c $^ -g -fPIC $(CXXFLAGS) $($@_CXXFLAGS)
+	$(QUIET) g++ -o $@ -c $< -g -fPIC $(CXXFLAGS) $($@_CXXFLAGS) -MMD -MF $(basename $@).dep -MP
 
 %.o: %.c
-	$(QUIET) gcc -o $@ -c $^ -g -fPIC $(CFLAGS) $($@_CFLAGS)
+	$(QUIET) gcc -o $@ -c $< -g -fPIC $(CFLAGS) $($@_CFLAGS) -MMD -MF $(basename $@).dep -MP
 
 
 # Generate Make rules for libraries.
@@ -28,7 +28,9 @@ define LIBS_template =
   # Propagate CXXFLAGS to the individual object files.
   $$(foreach obj, $$(_objs), $$(eval $$(obj)_CXXFLAGS=$$($(1)_CXXFLAGS)))
 
-  clean_list += $$(_lib) $$(_objs)
+  include $$(wildcard $$(_d)/*.dep)
+
+  clean_list += $$(_lib) $$(_objs) $$(_d)*.dep
   libs_list += $$(_lib)
 endef
 
@@ -48,7 +50,7 @@ define PROGRAMS_template =
   # Propagate CXXFLAGS to the individual object files.
   $$(foreach obj, $$(_objs), $$(eval $$(obj)_CXXFLAGS=$$($(1)_CXXFLAGS)))
 
-  clean_list += $$(_prog) $$(_objs)
+  clean_list += $$(_prog) $$(_objs) $$(_d)*.dep
   programs_list += $$(_prog)
 endef