Enable -Wformat=2 if it's supported.

grub-core/gfxmenu/gui_label.c

@@ -154,6 +154,8 @@ label_get_minimal_size (void *vself, unsigned *width, unsigned *height)
              + grub_font_get_descent (self->font));
 }
 
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+
 static void
 label_set_state (void *vself, int visible, int start __attribute__ ((unused)),
 		 int current, int end __attribute__ ((unused)))
@@ -235,6 +237,8 @@ label_set_property (void *vself, const char *name, const char *value)
   return GRUB_ERR_NONE;
 }
 
+#pragma GCC diagnostic error "-Wformat-nonliteral"
+
 static struct grub_gui_component_ops label_ops =
 {
   .destroy = label_destroy,

grub-core/gfxmenu/gui_progress_bar.c

@@ -183,6 +183,8 @@ draw_pixmap_bar (grub_gui_progress_bar_t self)
     }
 }
 
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+
 static void
 draw_text (grub_gui_progress_bar_t self)
 {
@@ -212,6 +214,8 @@ draw_text (grub_gui_progress_bar_t self)
     }
 }
 
+#pragma GCC diagnostic error "-Wformat-nonliteral"
+
 static void
 progress_bar_paint (void *vself, const grub_video_rect_t *region)
 {

grub-core/lib/legacy_parse.c

@@ -24,6 +24,8 @@
 #include <grub/i386/pc/vesa_modes_table.h>
 #include <grub/i18n.h>
 
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+
 struct legacy_command
 {
   const char *name;

grub-core/osdep/linux/hostdisk.c

@@ -237,6 +237,8 @@ have_devfs (void)
   return dev_devfsd_exists;
 }
 
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+
 static int
 grub_hostdisk_linux_find_partition (char *dev, grub_disk_addr_t sector)
 {
@@ -325,6 +327,8 @@ grub_hostdisk_linux_find_partition (char *dev, grub_disk_addr_t sector)
   return 0;
 }
 
+#pragma GCC diagnostic error "-Wformat-nonliteral"
+
 void
 grub_hostdisk_flush_initial_buffer (const char *os_dev)
 {

grub-core/partmap/msdos.c

@@ -229,6 +229,9 @@ grub_partition_msdos_iterate (grub_disk_t disk,
 }
 
 #ifdef GRUB_UTIL
+
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+
 static grub_err_t
 pc_partition_map_embed (struct grub_disk *disk, unsigned int *nsectors,
 			unsigned int max_nsectors,
@@ -401,6 +404,9 @@ pc_partition_map_embed (struct grub_disk *disk, unsigned int *nsectors,
 		     N_("your embedding area is unusually small.  "
 			"core.img won't fit in it."));
 }
+
+#pragma GCC diagnostic error "-Wformat-nonliteral"
+
 #endif
 
 

grub-core/term/tparm.c

@@ -158,6 +158,8 @@ get_space(grub_size_t need)
     }
 }
 
+#pragma GCC diagnostic ignored "-Wformat-nonliteral"
+
 static inline void
 save_text(const char *fmt, const char *s, int len)
 {
@@ -183,6 +185,8 @@ save_number(const char *fmt, int number, int len)
     out_used += grub_strlen(out_buff + out_used);
 }
 
+#pragma GCC diagnostic error "-Wformat-nonliteral"
+
 static inline void
 save_char(int c)
 {