tree-wide: remove align(8) for tags

This breaks the sizeof() property for many tags that I verify. Furthermore,
the builder structs already take care of any alignments when they construct
the MBI/MB header.

Author: phip1611

multiboot2-header/src/address.rs

@@ -6,7 +6,7 @@ use core::mem::size_of;
 /// other format. Required for legacy boot (BIOS).
 /// Determines load addresses.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct AddressHeaderTag {
     typ: HeaderTagType,
     flags: HeaderTagFlag,

multiboot2-header/src/end.rs

@@ -3,7 +3,7 @@ use core::mem::size_of;
 
 /// Terminates a list of optional tags in a Multiboot2 header.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct EndHeaderTag {
     // u16 value
     typ: HeaderTagType,

multiboot2-header/src/header.rs

@@ -227,7 +227,7 @@ impl core::error::Error for LoadError {}
 /// The "basic" Multiboot2 header. This means only the properties, that are known during
 /// compile time. All other information are derived during runtime from the size property.
 #[derive(Copy, Clone, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct Multiboot2BasicHeader {
     /// Must be the value of [`MULTIBOOT2_HEADER_MAGIC`].
     header_magic: u32,

multiboot2-header/src/module_align.rs

@@ -3,7 +3,7 @@ use core::mem::size_of;
 
 /// If this tag is present, provided boot modules must be page aligned.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct ModuleAlignHeaderTag {
     typ: HeaderTagType,
     flags: HeaderTagFlag,

multiboot2-header/src/relocatable.rs

@@ -20,7 +20,7 @@ pub enum RelocatableHeaderTagPreference {
 
 /// This tag indicates that the image is relocatable.
 #[derive(Copy, Clone, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct RelocatableHeaderTag {
     typ: HeaderTagType,
     flags: HeaderTagFlag,

multiboot2-header/src/tags.rs

@@ -64,7 +64,7 @@ pub enum HeaderTagFlag {
 /// that depend on the `typ` and the `size` field. All tags share the same beginning of the
 /// struct.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct HeaderTag {
     // u16 value
     typ: HeaderTagType,

multiboot2-header/src/uefi_bs.rs

@@ -4,7 +4,7 @@ use core::mem::size_of;
 /// This tag indicates that payload supports starting without terminating UEFI boot services.
 /// Or in other words: The payload wants to use UEFI boot services.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct EfiBootServiceHeaderTag {
     typ: HeaderTagType,
     flags: HeaderTagFlag,

multiboot2/src/boot_loader_name.rs

@@ -12,9 +12,8 @@ use {
 const METADATA_SIZE: usize = size_of::<TagTypeId>() + size_of::<u32>();
 
 /// The bootloader name tag.
-#[derive(ptr_meta::Pointee)]
-#[derive(PartialEq, Eq)]
-#[repr(C, align(8))]
+#[derive(ptr_meta::Pointee, PartialEq, Eq)]
+#[repr(C)]
 pub struct BootLoaderNameTag {
     typ: TagTypeId,
     size: u32,

multiboot2/src/command_line.rs

@@ -18,9 +18,8 @@ pub(crate) const METADATA_SIZE: usize = mem::size_of::<TagTypeId>() + mem::size_
 ///
 /// The string is a normal C-style UTF-8 zero-terminated string that can be
 /// obtained via the `command_line` method.
-#[derive(ptr_meta::Pointee)]
-#[derive(PartialEq, Eq)]
-#[repr(C, align(8))]
+#[derive(ptr_meta::Pointee, PartialEq, Eq)]
+#[repr(C)]
 pub struct CommandLineTag {
     typ: TagTypeId,
     size: u32,

multiboot2/src/efi.rs

@@ -10,7 +10,7 @@ use crate::builder::traits::StructAsBytes;
 
 /// EFI system table in 32 bit mode
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct EFISdt32 {
     typ: TagTypeId,
     size: u32,
@@ -42,7 +42,7 @@ impl StructAsBytes for EFISdt32 {
 
 /// EFI system table in 64 bit mode
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct EFISdt64 {
     typ: TagTypeId,
     size: u32,
@@ -74,7 +74,7 @@ impl StructAsBytes for EFISdt64 {
 
 /// Contains pointer to boot loader image handle.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct EFIImageHandle32 {
     typ: TagTypeId,
     size: u32,
@@ -106,7 +106,7 @@ impl StructAsBytes for EFIImageHandle32 {
 
 /// Contains pointer to boot loader image handle.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct EFIImageHandle64 {
     typ: TagTypeId,
     size: u32,

multiboot2/src/elf_sections.rs

@@ -15,9 +15,8 @@ const METADATA_SIZE: usize = size_of::<TagTypeId>() + 4 * size_of::<u32>();
 /// This tag contains section header table from an ELF kernel.
 ///
 /// The sections iterator is provided via the `sections` method.
-#[derive(ptr_meta::Pointee)]
-#[derive(PartialEq, Eq)]
-#[repr(C, align(8))]
+#[derive(ptr_meta::Pointee, PartialEq, Eq)]
+#[repr(C)]
 pub struct ElfSectionsTag {
     typ: TagTypeId,
     pub(crate) size: u32,

multiboot2/src/framebuffer.rs

@@ -51,9 +51,8 @@ const METADATA_SIZE: usize = size_of::<TagTypeId>()
     + 2 * size_of::<u8>();
 
 /// The VBE Framebuffer information Tag.
-#[derive(ptr_meta::Pointee)]
-#[derive(Eq)]
-#[repr(C, align(8))]
+#[derive(ptr_meta::Pointee, Eq)]
+#[repr(C)]
 pub struct FramebufferTag {
     typ: TagTypeId,
     size: u32,

multiboot2/src/image_load_addr.rs

@@ -8,7 +8,7 @@ use {
 /// If the image has relocatable header tag, this tag contains the image's
 /// base physical address.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct ImageLoadPhysAddr {
     typ: TagTypeId,
     size: u32,

multiboot2/src/lib.rs

@@ -173,8 +173,7 @@ pub unsafe fn load_with_offset(
 
 /// Error type that describes errors while loading/parsing a multiboot2 information structure
 /// from a given address.
-#[derive(Display)]
-#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
+#[derive(Display, Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub enum MbiLoadError {
     /// The address is invalid. Make sure that the address is 8-byte aligned,
     /// according to the spec.
@@ -386,7 +385,7 @@ impl BootInformation {
     /// use std::str::Utf8Error;
     /// use multiboot2::{Tag, TagTrait, TagTypeId};
     ///
-    /// #[repr(C, align(8))]
+    /// #[repr(C)]
     /// #[derive(multiboot2::Pointee)] // Only needed for DSTs.
     /// struct CustomTag {
     ///     // new type from the lib: has repr(u32)

multiboot2/src/memory_map.rs

@@ -22,9 +22,8 @@ const METADATA_SIZE: usize = mem::size_of::<TagTypeId>() + 3 * mem::size_of::<u3
 /// This tag may not be provided by some boot loaders on EFI platforms if EFI
 /// boot services are enabled and available for the loaded image (The EFI boot
 /// services tag may exist in the Multiboot2 boot information structure).
-#[derive( ptr_meta::Pointee)]
-#[derive(Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[derive(ptr_meta::Pointee, Debug, PartialEq, Eq)]
+#[repr(C)]
 pub struct MemoryMapTag {
     typ: TagTypeId,
     size: u32,
@@ -82,7 +81,7 @@ impl StructAsBytes for MemoryMapTag {
 
 /// A memory area entry descriptor.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct MemoryArea {
     base_addr: u64,
     length: u64,
@@ -192,7 +191,7 @@ impl<'a> Iterator for MemoryAreaIter<'a> {
 /// Nowadays, much bigger chunks of continuous memory are available at higher
 /// addresses, but the Multiboot standard still references those two terms.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct BasicMemoryInfoTag {
     typ: TagTypeId,
     size: u32,
@@ -232,7 +231,7 @@ const EFI_METADATA_SIZE: usize = mem::size_of::<TagTypeId>() + 3 * mem::size_of:
 #[derive(ptr_meta::Pointee)]
 // #[derive(Debug, PartialEq, Eq)] // wait for uefi-raw 0.3.0
 #[derive(Debug)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct EFIMemoryMapTag {
     typ: TagTypeId,
     size: u32,
@@ -300,7 +299,7 @@ impl StructAsBytes for EFIMemoryDesc {
 
 /// EFI ExitBootServices was not called
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct EFIBootServicesNotExited {
     typ: TagTypeId,
     size: u32,

multiboot2/src/module.rs

@@ -14,9 +14,8 @@ const METADATA_SIZE: usize = size_of::<TagTypeId>() + 3 * size_of::<u32>();
 
 /// This tag indicates to the kernel what boot module was loaded along with
 /// the kernel image, and where it can be found.
-#[derive(ptr_meta::Pointee)]
-#[derive(PartialEq, Eq)]
-#[repr(C, align(8))]
+#[derive(ptr_meta::Pointee, PartialEq, Eq)]
+#[repr(C)]
 pub struct ModuleTag {
     typ: TagTypeId,
     size: u32,

multiboot2/src/rsdp.rs

@@ -24,7 +24,7 @@ const RSDPV1_LENGTH: usize = 20;
 
 /// This tag contains a copy of RSDP as defined per ACPI 1.0 specification.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct RsdpV1Tag {
     typ: TagTypeId,
     size: u32,
@@ -97,7 +97,7 @@ impl StructAsBytes for RsdpV1Tag {
 
 /// This tag contains a copy of RSDP as defined per ACPI 2.0 or later specification.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct RsdpV2Tag {
     typ: TagTypeId,
     size: u32,

multiboot2/src/smbios.rs

@@ -11,9 +11,8 @@ const METADATA_SIZE: usize = core::mem::size_of::<TagTypeId>()
     + core::mem::size_of::<u8>() * 8;
 
 /// This tag contains a copy of SMBIOS tables as well as their version.
-#[derive(ptr_meta::Pointee)]
-#[derive(PartialEq, Eq)]
-#[repr(C, align(8))]
+#[derive(ptr_meta::Pointee, PartialEq, Eq)]
+#[repr(C)]
 pub struct SmbiosTag {
     typ: TagTypeId,
     size: u32,

multiboot2/src/vbe_info.rs

@@ -4,7 +4,7 @@ use core::fmt;
 /// This tag contains VBE metadata, VBE controller information returned by the
 /// VBE Function 00h and VBE mode information returned by the VBE Function 01h.
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
-#[repr(C, align(8))]
+#[repr(C)]
 pub struct VBEInfoTag {
     typ: TagTypeId,
     length: u32,