--- a/m4/gauche.m4
+++ b/m4/gauche.m4
@@ -103,13 +103,10 @@
   AS_CASE(["$target"],
 	  [i686-*], [I686OPT="-DUSE_I686_PREFETCH"])
   AS_CASE(["$CC"],
-	  [gcc*], [ dnl some systems may have gcc-2.95, gcc-3, etc.
+	  [*gcc*], [ dnl some systems may have gcc-2.95, gcc-3, etc.
 		  AS_CASE(["$target"],
 			  [*mingw*], [],
-				     [GCCOPT="-fomit-frame-pointer"])
-		  AS_CASE(["$target"],
-			  [i586-*], [GCCOPT="$GCCOPT -march=i586"],
-			  [i686-*], [GCCOPT="$GCCOPT -march=i686"])])])
+				     [GCCOPT="-fomit-frame-pointer"])])])
 OPTFLAGS="$GCCOPT $I686OPT"
 AC_SUBST(OPTFLAGS)
 ])
@@ -150,7 +147,7 @@
 dnl
 AC_DEFUN([AC_GAUCHE_MAKE_GPD],
 	 [
-GAUCHE_PACKAGE_CONFIGURE_ARGS=`echo "$ac_configure_args" | sed 's/@<:@\\"\`\$@:>@/\\\\&/g'`
+GAUCHE_PACKAGE_CONFIGURE_ARGS=`echo "$ac_configure_args" | sed 's/@<:@\$\\"\`@:>@/\\\\&/g'`
 AC_MSG_NOTICE([creating ${PACKAGE_NAME}.gpd])
 $GAUCHE_PACKAGE make-gpd "$PACKAGE_NAME" \
   -version "$PACKAGE_VERSION" \