Re: [XEN PATCH 01/11] x86/efi: move variable declaration to address MISRA C:2012 Rule 2.1

[Nicola Vetrini]

On 03/08/2023 10:57, Jan Beulich wrote:

On 03.08.2023 04:08, Stefano Stabellini wrote:

On Wed, 2 Aug 2023, Nicola Vetrini wrote:

The variable declaration is moved where it's actually used, rather
than being declared in the switch before any clause, thus being
classified as unreachable code.

No functional changes.

Signed-off-by: Nicola Vetrini <nicola.vetr...@bugseng.com>
---
 xen/arch/x86/efi/efi-boot.h | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/xen/arch/x86/efi/efi-boot.h b/xen/arch/x86/efi/efi-boot.h

index 92f4cfe8bd..b00441b1a2 100644
--- a/xen/arch/x86/efi/efi-boot.h
+++ b/xen/arch/x86/efi/efi-boot.h
@@ -390,8 +390,6 @@ static void __init efi_arch_edd(void)
         {
             switch ( DevicePathType(devp.DevPath) )
             {
-                const u8 *p;
-
             case ACPI_DEVICE_PATH:

if ( state != root || boot_edd_info_nr > EDD_INFO_MAX )

                     break;
@@ -463,7 +461,8 @@ static void __init efi_arch_edd(void)
                 params->device_path_info_length =
                     sizeof(struct edd_device_params) -
                     offsetof(struct edd_device_params, key);

- for ( p = (const u8 *)&params->key; p < &params->checksum; ++p )

+                for ( const u8 *p = (const u8 *)&params->key;
+                      p < &params->checksum; ++p )

In Xen we don't mix declaration and code. So the following is not
something we use:

  for (int i = 0; i < 10; i++)

You're aware that we gained a couple of such uses already? I also think
that when we discussed this we said this style could be at least
okay-ish (until formalized in ./CODING_STYLE).

What I'm unhappy with here is the retaining of u8, when it could easily
become uint8_t at this occasion.

Jan

Sure

--
Nicola Vetrini, BSc
Software Engineer, BUGSENG srl (https://bugseng.com)