diff -u -r automake_patch2/ChangeLog automake_patch3/ChangeLog
--- automake_patch2/ChangeLog	Thu Aug  2 01:39:14 2001
+++ automake_patch3/ChangeLog	Thu Aug  2 02:34:28 2001
@@ -1,5 +1,14 @@
 2001-08-02  Richard Boulton <address@hidden>
 
+	* automake.in (value_to_list): Check for whether $from is defined,
+	rather than whether it is true, so that empty $froms are allowed in
+	substitution reference patterns.
+
+	* tests/substref.test: New file: test behavior of substitution
+	references when the $from side of the substitution is empty.
+
+2001-08-02  Richard Boulton <address@hidden>
+
 	* automake.in (variable_conditions_sub): Handle variable
 	substitution refs when computing conditions based on subvariable
 	conditions.  Fixes substitution refs of system variables when sub
diff -u -r automake_patch2/automake.in automake_patch3/automake.in
--- automake_patch2/automake.in	Thu Aug  2 01:08:28 2001
+++ automake_patch3/automake.in	Thu Aug  2 02:21:55 2001
@@ -6140,7 +6140,7 @@
 	    @temp_list = &variable_value_as_list_worker ($1, $cond, $var);
 
 	    # Now rewrite the value if appropriate.
-	    if ($from)
+	    if (defined $from)
 	    {
 		grep (s/$from$/$to/, @temp_list);
 	    }
diff -u -r automake_patch2/tests/Makefile.am automake_patch3/tests/Makefile.am
--- automake_patch2/tests/Makefile.am	Thu Aug  2 01:42:44 2001
+++ automake_patch3/tests/Makefile.am	Thu Aug  2 02:31:44 2001
@@ -278,6 +278,7 @@
 subobj7.test \
 subobj8.test \
 subst.test \
+substref.test \
 substtarg.test \
 suffix.test \
 suffix2.test \
diff -u -r automake_patch2/tests/Makefile.in automake_patch3/tests/Makefile.in
--- automake_patch2/tests/Makefile.in	Thu Aug  2 01:42:51 2001
+++ automake_patch3/tests/Makefile.in	Thu Aug  2 02:31:48 2001
@@ -346,6 +346,7 @@
 subobj7.test \
 subobj8.test \
 subst.test \
+substref.test \
 substtarg.test \
 suffix.test \
 suffix2.test \
diff -u -r automake_patch2/tests/substref.test automake_patch3/tests/substref.test
--- automake_patch2/tests/substref.test	Thu Jan  1 01:00:00 1970
+++ automake_patch3/tests/substref.test	Thu Aug  2 02:25:43 2001
@@ -0,0 +1,46 @@
+#! /bin/sh
+
+# Test for bug in variable substitution references when left hand pattern is
+# null.
+# Report from Richard Boulton
+
+. $srcdir/defs || exit 1
+
+cat > configure.in << 'END'
+AC_INIT(hello.c)
+AM_INIT_AUTOMAKE(hello,0.23)
+AC_PROG_CC
+AC_OUTPUT(Makefile)
+END
+
+cat > hello.c << 'END'
+END
+
+cat > Makefile.am << 'END'
+
+var1 = dlmain
+
+var2 = $(var1:=.)
+
+helldl_SOURCES = $(var2:=c)
+
+echorule:
+	@echo $(helldl_SOURCES) $(helldl_OBJECTS)
+
+bin_PROGRAMS = helldl
+END
+
+$needs_autoconf
+(gcc -v) > /dev/null 2>&1 || exit 77
+
+set -e
+
+$ACLOCAL
+$AUTOCONF
+$AUTOMAKE -a
+
+CC='gcc' ./configure
+
+val=`$MAKE echorule`;
+echo $val
+test "x$val" = "xdlmain.c dlmain.o"