f2fs: Disable gcc9 -Waddress-of-packed-member

Disable the -Wadress-of-packaed-member diagnostic for the grub_f2fs_label
function since the result is found to be false postive.

A pointer to the 'volume_name' member of 'struct grub_f2fs_superblock' is
guaranteed to be aligned as the offset of 'volume_name' within the struct
is dividable by the natural alignment on both 32- and 64-bit targets.

grub-core/fs/f2fs.c: In function ‘grub_f2fs_label’:
grub-core/fs/f2fs.c:1253:60: error: taking address of packed member of ‘struct grub_f2fs_superblock’ may result in an unaligned pointer value [-Werror=address-of-packed-member]
 1253 |     *label = (char *) grub_f2fs_utf16_to_utf8 (data->sblock.volume_name);
      |                                                ~~~~~~~~~~~~^~~~~~~~~~~~
cc1: all warnings being treated as errors

Reported-by: Neil MacLeod <neil@nmacleod.com>
Signed-off-by: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Tested-by: Neil MacLeod <neil@nmacleod.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>

diff --git a/grub-core/fs/f2fs.c b/grub-core/fs/f2fs.c
index bb28b291bd9bcc677b136abecb6a8941add391bc..8a9992ca9e45d8e6c981b6887e6833fa638869b6 100644 (file)
--- a/grub-core/fs/f2fs.c
+++ b/grub-core/fs/f2fs.c
@@ -1240,6 +1240,11 @@ grub_f2fs_utf16_to_utf8 (grub_uint16_t *in_buf_le)
   return out_buf;
 }
 
+#if __GNUC__ >= 9
+#pragma GCC diagnostic push
+#pragma GCC diagnostic ignored "-Waddress-of-packed-member"
+#endif
+
 static grub_err_t
 grub_f2fs_label (grub_device_t device, char **label)
 {
@@ -1260,6 +1265,10 @@ grub_f2fs_label (grub_device_t device, char **label)
   return grub_errno;
 }
 
+#if __GNUC__ >= 9
+#pragma GCC diagnostic pop
+#endif
+
 static grub_err_t
 grub_f2fs_uuid (grub_device_t device, char **uuid)
 {