diff --git a/ChangeLog b/ChangeLog
index 7e83dd8d1..b2474813f 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+2003-01-05  Yoshinori K. Okuji  <okuji@enbug.org>
+
+	* configure.in (CFLAGS): When the default CFLAGS is used,
+	eliminate -O2 and -g from CFLAGS, because Autoconf may
+	automatically set CFLAGS to them.
+
 2003-01-02  Yoshinori K. Okuji  <okuji@enbug.org>
 
 	From Jeremy Katz:
diff --git a/configure b/configure
index 53b59cd8f..e1c0b1662 100644
--- a/configure
+++ b/configure
@@ -2917,7 +2917,8 @@ fi
 # optimization flags
 if test "x$ac_cv_c_compiler_gnu" = xyes; then
   if test "x$default_CFLAGS" = xyes; then
-    CFLAGS="$CFLAGS -g"
+    # Autoconf may set CFLAGS to -O2 and/or -g. So eliminate them.
+    CFLAGS="`echo $CFLAGS | sed -e 's/-g//g' -e 's/-O[0-9]/g'` -g"
     # If the user specify the directory for binutils, add the option `-B'.
     if test "x$with_binutils" != x; then
       CFLAGS="-B$with_binutils/ $CFLAGS"
diff --git a/configure.in b/configure.in
index 83d1634eb..767f0acc5 100644
--- a/configure.in
+++ b/configure.in
@@ -77,7 +77,8 @@ fi
 # optimization flags
 if test "x$ac_cv_prog_gcc" = xyes; then
   if test "x$default_CFLAGS" = xyes; then
-    CFLAGS="$CFLAGS -g"
+    # Autoconf may set CFLAGS to -O2 and/or -g. So eliminate them.
+    CFLAGS="`echo $CFLAGS | sed -e 's/-g//g' -e 's/-O[[0-9]]/g'` -g"
     # If the user specify the directory for binutils, add the option `-B'.
     if test "x$with_binutils" != x; then
       CFLAGS="-B$with_binutils/ $CFLAGS"
diff --git a/stage2/fsys_fat.c b/stage2/fsys_fat.c
index 286d4a45f..27eafc29e 100644
--- a/stage2/fsys_fat.c
+++ b/stage2/fsys_fat.c
@@ -224,6 +224,9 @@ fat_read (char *buf, int len)
 	  else if (FAT_SUPER->fat_size == 4)
 	    next_cluster &= 0xFFFF;
 	  
+	  grub_printf ("%s:%d: next_cluster=%d\n",
+		       __FILE__, __LINE__, next_cluster);
+	  
 	  if (next_cluster >= FAT_SUPER->clust_eof_marker)
 	    return ret;
 	  if (next_cluster < 2 || next_cluster >= FAT_SUPER->num_clust)