diff --git a/ChangeLog b/ChangeLog
index a56bee8748..447240ceb3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Sun Sep  8 21:29:25 2002  WATANABE Hirofumi  <eban@ruby-lang.org>
+
+	* time.c (time_free): prototype; struct time_object -> void *.
+	  avoid GCC warnings.
+
+	* lib/mkmf.rb, ext/extmk.rb ($LINK, $CPP): move to lib/mkmf.rb.
+
 Sun Sep  8 19:02:28 2002  NAKAMURA Usaku <usa@ruby-lang.org>
 
 	* time.c: prototype; time_free() to avoid VC++ warnings.
diff --git a/ext/extmk.rb b/ext/extmk.rb
index 77757dc830..ca46e25beb 100644
--- a/ext/extmk.rb
+++ b/ext/extmk.rb
@@ -32,19 +32,17 @@ $extlist = []
 $:.replace ["."]
 require 'rbconfig'
 
-$top_srcdir = Config::CONFIG["srcdir"]
+srcdir = Config::CONFIG["srcdir"]
 
-$:.replace [$top_srcdir, $top_srcdir+"/lib", "."]
+$:.replace [srcdir, srcdir+"/lib", "."]
 
 require 'mkmf'
 require 'find'
 require 'ftools'
 require 'shellwords'
 
-$topdir = File.expand_path(".")
-
-$LINK = "#{CONFIG['CC']} #{OUTFLAG}conftest -I#$topdir -I#$top_srcdir #{CFLAGS} %s %s #{CONFIG['LDFLAGS']} %s conftest.c %s %s #{CONFIG['LIBS']}"
-$CPP = "#{CONFIG['CPP']} #{CONFIG['CPPFLAGS']} %s -I#$topdir -I#$top_srcdir #{CFLAGS} %s %s %s conftest.c"
+$topdir = $hdrdir = File.expand_path(".")
+$top_srcdir = srcdir
 
 Object.class_eval do remove_method :create_makefile end
 
diff --git a/lib/mkmf.rb b/lib/mkmf.rb
index a0e01c47c7..fb2ce78ee7 100644
--- a/lib/mkmf.rb
+++ b/lib/mkmf.rb
@@ -68,7 +68,7 @@ else
   STDERR.print "can't find header files for ruby.\n"
   exit 1
 end
-$topdir = $hdrdir
+$topdir = $top_srcdir = $hdrdir
 # $hdrdir.gsub!('/', '\\') if RUBY_PLATFORM =~ /mswin32|bccwin32/
 
 CFLAGS = CONFIG["CFLAGS"]
@@ -89,9 +89,9 @@ else
   CPPOUTFILE = '-o conftest.i'
 end
 
-$LINK = "#{CONFIG['CC']} #{OUTFLAG}conftest -I#{$hdrdir} #{CFLAGS} %s %s #{CONFIG['LDFLAGS']} %s conftest.c %s %s #{CONFIG['LIBS']}"
-$CC = "#{CONFIG['CC']} -c #{CONFIG['CPPFLAGS']} %s -I#{$hdrdir} #{CFLAGS} %s %s conftest.c"
-$CPP = "#{CONFIG['CPP']} #{CONFIG['CPPFLAGS']} %s -I#{$hdrdir} #{CFLAGS} %s %s %s conftest.c"
+$LINK = "#{CONFIG['CC']} #{OUTFLAG}conftest -I#{$hdrdir} -I#{$top_srcdir} #{CFLAGS} %s %s #{CONFIG['LDFLAGS']} %s conftest.c %s %s #{CONFIG['LIBS']}"
+$CC = "#{CONFIG['CC']} -c #{CONFIG['CPPFLAGS']} %s -I#{$hdrdir} -I#{$top_srcdir} #{CFLAGS} %s %s conftest.c"
+$CPP = "#{CONFIG['CPP']} #{CONFIG['CPPFLAGS']} %s -I#{$hdrdir} -I#{$top_srcdir} #{CFLAGS} %s %s %s conftest.c"
 
 def rm_f(*files)
   targets = []
diff --git a/time.c b/time.c
index ff66acf1e3..01d370ed79 100644
--- a/time.c
+++ b/time.c
@@ -43,11 +43,11 @@ struct time_object {
 #define GetTimeval(obj, tobj) \
     Data_Get_Struct(obj, struct time_object, tobj)
 
-static void time_free _((struct time_object *));
+static void time_free _((void *));
 
 static void
 time_free(tobj)
-    struct time_object *tobj;
+    void *tobj;
 {
     if (tobj) free(tobj);
 }