diff --git a/ChangeLog b/ChangeLog
index d05ae44843..1ae6576d43 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Sat Nov 15 19:48:59 2014  NAKAMURA Usaku  <usa@ruby-lang.org>
+
+	* lib/mkmf.rb (depend_rules): support comments during a line.
+
+	* lib/mkmf.rb (depend_rules): apply RULE_SUBST even if the dependency
+	  file contains path.
+
 Sat Nov 15 19:25:46 2014  Tanaka Akira  <akr@fsij.org>
 
 	* common.mk: Remove comments in Dependency lines.
diff --git a/lib/mkmf.rb b/lib/mkmf.rb
index 1eb52047a3..513dff3583 100644
--- a/lib/mkmf.rb
+++ b/lib/mkmf.rb
@@ -2051,7 +2051,10 @@ RULES
         implicit = [[m[1], m[2]], [m.post_match]]
         next
       elsif RULE_SUBST and /\A(?!\s*\w+\s*=)[$\w][^#]*:/ =~ line
-        line.gsub!(%r"(\s)(?!\.)([^$(){}+=:\s\/\\,]+)(?=\s|\z)") {$1 + RULE_SUBST % $2}
+        line.sub!(/\s*\#.*$/, '')
+        comment = $&
+        line.gsub!(%r"(\s)(?!\.)([^$(){}+=:\s\\,]+)(?=\s|\z)") {$1 + RULE_SUBST % $2}
+        line = line.chomp + comment + "\n" if comment
       end
       depout << line
     end