From 5b29eba636c3c61ff5722da9201880fcec0f18d1 Mon Sep 17 00:00:00 2001
From: Wei Liu <liuwe@microsoft.com>
Date: Thu, 9 Jan 2025 01:49:16 +0000
Subject: [PATCH] block: vhdx: use C ABI-qualification for packed structures

This fixes the following issue from beta Clippy:

error: item uses `packed` representation without ABI-qualification
Error:    --> block/src/vhdx/vhdx_header.rs:333:1
    |
331 |   #[repr(packed)]
    |          ------ `packed` representation set here
332 |   #[derive(Clone, Copy, Debug)]
333 | / pub struct RegionTableEntry {
334 | |     pub guid: Uuid,
335 | |     pub file_offset: u64,
336 | |     pub length: u32,
337 | |     pub required: u32,
338 | | }
    | |_^
    |
    = warning: unqualified `#[repr(packed)]` defaults to `#[repr(Rust, packed)]`, which has no stable ABI
    = help: qualify the desired ABI explicity via `#[repr(C, packed)]` or `#[repr(Rust, packed)]`
    = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#repr_packed_without_abi

Signed-off-by: Wei Liu <liuwe@microsoft.com>
---
 block/src/vhdx/vhdx_header.rs   | 6 +++---
 block/src/vhdx/vhdx_metadata.rs | 4 ++--
 2 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/block/src/vhdx/vhdx_header.rs b/block/src/vhdx/vhdx_header.rs
index e7863d0da..bed5418d8 100644
--- a/block/src/vhdx/vhdx_header.rs
+++ b/block/src/vhdx/vhdx_header.rs
@@ -110,7 +110,7 @@ impl FileTypeIdentifier {
     }
 }
 
-#[repr(packed)]
+#[repr(C, packed)]
 #[derive(Clone, Copy, Debug)]
 pub struct Header {
     pub signature: u32,
@@ -203,7 +203,7 @@ impl Header {
     }
 }
 
-#[repr(packed)]
+#[repr(C, packed)]
 #[derive(Clone, Copy, Debug)]
 struct RegionTableHeader {
     pub signature: u32,
@@ -328,7 +328,7 @@ impl RegionInfo {
     }
 }
 
-#[repr(packed)]
+#[repr(C, packed)]
 #[derive(Clone, Copy, Debug)]
 pub struct RegionTableEntry {
     pub guid: Uuid,
diff --git a/block/src/vhdx/vhdx_metadata.rs b/block/src/vhdx/vhdx_metadata.rs
index 6284a9a5b..47cc2ff68 100644
--- a/block/src/vhdx/vhdx_metadata.rs
+++ b/block/src/vhdx/vhdx_metadata.rs
@@ -267,7 +267,7 @@ impl DiskSpec {
     }
 }
 
-#[repr(packed)]
+#[repr(C, packed)]
 #[derive(Default, Debug, Clone, Copy)]
 struct MetadataTableHeader {
     signature: u64,
@@ -298,7 +298,7 @@ impl MetadataTableHeader {
     }
 }
 
-#[repr(packed)]
+#[repr(C, packed)]
 #[derive(Default, Debug, Clone, Copy)]
 pub struct MetadataTableEntry {
     item_id: Uuid,