diff --git a/conf/Makefile.common b/conf/Makefile.common
index 11296b550..6db04343a 100644
--- a/conf/Makefile.common
+++ b/conf/Makefile.common
@@ -65,7 +65,7 @@ grubconfdir = $(sysconfdir)/grub.d
 platformdir = $(pkglibdir)/$(target_cpu)-$(platform)
 starfielddir = $(pkgdatadir)/themes/starfield
 
-CFLAGS_GNULIB = -Wno-undef -Wno-sign-compare -Wno-unused -Wno-unused-parameter -Wno-redundant-decls -Wno-unreachable-code -Wno-conversion
+CFLAGS_GNULIB = -Wno-undef -Wno-sign-compare -Wno-unused -Wno-unused-parameter -Wno-redundant-decls -Wno-unreachable-code -Wno-conversion -Wno-maybe-uninitialized
 CPPFLAGS_GNULIB = -I$(top_builddir)/grub-core/gnulib -I$(top_srcdir)/grub-core/gnulib
 
 CFLAGS_POSIX = -fno-builtin
diff --git a/grub-core/commands/i386/cmostest.c b/grub-core/commands/i386/cmostest.c
index e5dea0769..c839b704d 100644
--- a/grub-core/commands/i386/cmostest.c
+++ b/grub-core/commands/i386/cmostest.c
@@ -45,7 +45,7 @@ static grub_err_t
 grub_cmd_cmostest (struct grub_command *cmd __attribute__ ((unused)),
 		   int argc, char *argv[])
 {
-  int byte, bit;
+  int byte = 0, bit = 0;
   grub_err_t err;
   grub_uint8_t value;
 
@@ -67,7 +67,7 @@ static grub_err_t
 grub_cmd_cmosclean (struct grub_command *cmd __attribute__ ((unused)),
 		    int argc, char *argv[])
 {
-  int byte, bit;
+  int byte = 0, bit = 0;
   grub_err_t err;
   grub_uint8_t value;
 
@@ -85,7 +85,7 @@ static grub_err_t
 grub_cmd_cmosset (struct grub_command *cmd __attribute__ ((unused)),
 		    int argc, char *argv[])
 {
-  int byte, bit;
+  int byte = 0, bit = 0;
   grub_err_t err;
   grub_uint8_t value;
 
diff --git a/grub-core/fs/ntfscomp.c b/grub-core/fs/ntfscomp.c
index 2e1ce51a8..3cd97d337 100644
--- a/grub-core/fs/ntfscomp.c
+++ b/grub-core/fs/ntfscomp.c
@@ -104,7 +104,7 @@ decomp_block (struct grub_ntfs_comp *cc, grub_uint8_t *dest)
 	      if (tag & 1)
 		{
 		  grub_uint32_t i, len, delta, code, lmask, dshift;
-		  grub_uint16_t word;
+		  grub_uint16_t word = 0;
 
 		  if (decomp_get16 (cc, &word))
 		    return grub_errno;
diff --git a/grub-core/fs/zfs/zfs.c b/grub-core/fs/zfs/zfs.c
index c4ead29fb..6e1fff9e9 100644
--- a/grub-core/fs/zfs/zfs.c
+++ b/grub-core/fs/zfs/zfs.c
@@ -3132,7 +3132,7 @@ make_mdn (dnode_end_t * mdn, struct grub_zfs_data *data)
 {
   void *osp;
   blkptr_t *bp;
-  grub_size_t ospsize;
+  grub_size_t ospsize = 0;
   grub_err_t err;
 
   grub_dprintf ("zfs", "endian = %d\n", mdn->endian);