diff --git a/include/kernaux/multiboot2.h b/include/kernaux/multiboot2.h
index ba30642..6b950e0 100644
--- a/include/kernaux/multiboot2.h
+++ b/include/kernaux/multiboot2.h
@@ -10,14 +10,16 @@ extern "C" {
  *********************/
 
 struct KernAux_Multiboot2 {
-    unsigned int total_size;
-    unsigned int reserved1;
-};
+    unsigned int total_size : 32;
+    unsigned int reserved1  : 32;
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_TagBase {
-    unsigned int type;
-    unsigned int size;
-};
+    unsigned int type : 32;
+    unsigned int size : 32;
+}
+__attribute__((packed));
 
 /******************
  * Tag structures *
@@ -29,7 +31,8 @@ struct KernAux_Multiboot2_Tag_BootCmdLine {
     struct KernAux_Multiboot2_TagBase base;
 
     char cmdline[];
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_BootLoaderName {
     // type = 2
@@ -37,135 +40,147 @@ struct KernAux_Multiboot2_Tag_BootLoaderName {
     struct KernAux_Multiboot2_TagBase base;
 
     char name[];
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_Module {
     // type = 3
     // size = ?
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned int mod_start;
-    unsigned int mod_end;
+    unsigned int mod_start : 32;
+    unsigned int mod_end   : 32;
 
     char cmdline[];
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_BasicMemoryInfo {
     // type = 4
     // size = 16
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned int mem_lower;
-    unsigned int mem_upper;
-};
+    unsigned int mem_lower : 32;
+    unsigned int mem_upper : 32;
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_BIOSBootDevice {
     // type = 5
     // size = 20
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned int bios_dev;
-    unsigned int partition;
-    unsigned int sub_partition;
-};
+    unsigned int bios_dev      : 32;
+    unsigned int partition     : 32;
+    unsigned int sub_partition : 32;
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_MemoryMap {
     // type = 5
     // size = ?
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned int size;
-    unsigned int entry_size;
-    unsigned int entry_version;
+    unsigned int size          : 32;
+    unsigned int entry_size    : 32;
+    unsigned int entry_version : 32;
 
     unsigned char data[];
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_VBEInfo {
     // type = 7
     // size = 784
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned short vbe_mode;
-    unsigned short vbe_interface_seg;
-    unsigned short vbe_interface_off;
-    unsigned short vbe_interface_len;
+    unsigned short vbe_mode          : 16;
+    unsigned short vbe_interface_seg : 16;
+    unsigned short vbe_interface_off : 16;
+    unsigned short vbe_interface_len : 16;
     unsigned char vbe_control_info[512];
     unsigned char vbe_mode_info[256];
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_FramebufferInfo {
     // type = 8
     // size = ?
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned long long framebuffer_addr;
-    unsigned int framebuffer_pitch;
-    unsigned int framebuffer_width;
-    unsigned int framebuffer_height;
-    unsigned char framebuffer_bpp;
-    unsigned char framebuffer_type;
-    unsigned char reserved1;
+    unsigned long long framebuffer_addr : 64;
+    unsigned int framebuffer_pitch      : 32;
+    unsigned int framebuffer_width      : 32;
+    unsigned int framebuffer_height     : 32;
+    unsigned char framebuffer_bpp       : 8;
+    unsigned char framebuffer_type      : 8;
+    unsigned char reserved1             : 8;
 
     unsigned char data[];
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_ELFSymbols {
     // type = 9
     // size = ?
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned short num;
-    unsigned short ent_size;
-    unsigned short shndx;
-    unsigned short reserved1;
+    unsigned short num       : 16;
+    unsigned short ent_size  : 16;
+    unsigned short shndx     : 16;
+    unsigned short reserved1 : 16;
 
     unsigned char section_headers[];
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_APMTable {
     // type = 10
     // size = 20
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned short version;
-    unsigned short cseg;
-    unsigned int offset;
-    unsigned short cseg_16;
-    unsigned short dseg;
-    unsigned short flags;
-    unsigned short cseg_len;
-    unsigned short cseg_16_len;
-    unsigned short dseg_len;
-};
+    unsigned short version     : 16;
+    unsigned short cseg        : 16;
+    unsigned int offset        : 32;
+    unsigned short cseg_16     : 16;
+    unsigned short dseg        : 16;
+    unsigned short flags       : 16;
+    unsigned short cseg_len    : 16;
+    unsigned short cseg_16_len : 16;
+    unsigned short dseg_len    : 16;
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_EFI32bitSystemTablePointer {
     // type = 11
     // size = 12
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned int pointer;
-};
+    unsigned int pointer : 32;
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_EFI64bitSystemTablePointer {
     // type = 12
     // size = 16
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned long long pointer;
-};
+    unsigned long long pointer : 64;
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_SMBIOSTables {
     // type = 13
     // size = ?
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned char major;
-    unsigned char minor;
+    unsigned char major : 8;
+    unsigned char minor : 8;
     unsigned char reserved1[6];
 
     unsigned char data[];
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_ACPIOldRSDP {
     // type = 14
@@ -173,7 +188,8 @@ struct KernAux_Multiboot2_Tag_ACPIOldRSDP {
     struct KernAux_Multiboot2_TagBase base;
 
     unsigned char data[];
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_ACPINewRSDP {
     // type = 15
@@ -181,7 +197,8 @@ struct KernAux_Multiboot2_Tag_ACPINewRSDP {
     struct KernAux_Multiboot2_TagBase base;
 
     unsigned char data[];
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_NetworkingInfo {
     // type = 16
@@ -189,59 +206,66 @@ struct KernAux_Multiboot2_Tag_NetworkingInfo {
     struct KernAux_Multiboot2_TagBase base;
 
     unsigned char data[];
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_EFIMemoryMap {
     // type = 17
     // size = ?
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned int descriptor_size;
-    unsigned int descriptor_version;
+    unsigned int descriptor_size    : 32;
+    unsigned int descriptor_version : 32;
 
     unsigned char data[];
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_EFIBootServicesNotTerminated {
     // type = 18
     // size = 8
     struct KernAux_Multiboot2_TagBase base;
-};
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_EFI32bitImageHandlePointer {
     // type = 19
     // size = 12
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned int pointer;
-};
+    unsigned int pointer : 32;
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_EFI64bitImageHandlePointer {
     // type = 20
     // size = 16
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned long long pointer;
-};
+    unsigned long long pointer : 64;
+}
+__attribute__((packed));
 
 struct KernAux_Multiboot2_Tag_ImageLoadBasePhysAddr {
     // type = 21
     // size = 12
     struct KernAux_Multiboot2_TagBase base;
 
-    unsigned int load_base_addr;
-};
+    unsigned int load_base_addr : 32;
+}
+__attribute__((packed));
 
 /*************************
  * Additional structures *
  *************************/
 
 struct KernAux_Multiboot2_Tag_MemoryMap_EntryBase {
-    unsigned long long base_addr;
-    unsigned long long length;
-    unsigned int type;
-    unsigned int reserved1;
-};
+    unsigned long long base_addr : 64;
+    unsigned long long length    : 64;
+    unsigned int type            : 32;
+    unsigned int reserved1       : 32;
+}
+__attribute__((packed));
 
 #ifdef __cplusplus
 }