Specify Multiboot 2 header in C

src/Makefile

@@ -20,7 +20,7 @@ CPPFLAGS =        \
 	$(MRUBY_FLAGS)  \
 	-DKERNAUX_DEBUG \
 
-OBJS = start.S.o main.c.o libc.c.o logger.c.o panic.c.o
+OBJS = multiboot2.c.o start.S.o main.c.o libc.c.o logger.c.o panic.c.o
 
 all: $(MRUBYVISOR)
 

src/linker.ld

@@ -14,7 +14,7 @@ SECTIONS
 
     .text BLOCK(4K) : ALIGN(4K)
     {
-        *(.multiboot)
+        *(.multiboot2)
         *(.text)
     }
 

src/multiboot2.c

@@ -0,0 +1,34 @@
+#include <kernaux/multiboot2.h>
+
+#include <kernaux/macro/packing_start.run>
+
+__attribute__((
+    section(".multiboot2"),
+    used,
+    aligned(KERNAUX_MULTIBOOT2_HEADER_ALIGN)
+))
+const struct {
+    struct KernAux_Multiboot2_Header header;
+    struct KernAux_Multiboot2_HTag_None tag_none;
+}
+KERNAUX_PACKED
+multiboot2 = {
+    .header = {
+        .magic = KERNAUX_MULTIBOOT2_HEADER_MAGIC,
+        .arch = KERNAUX_MULTIBOOT2_HEADER_ARCH_I386,
+        .total_size = sizeof(multiboot2),
+        .checksum = KERNAUX_MULTIBOOT2_HEADER_CHECKSUM(
+            KERNAUX_MULTIBOOT2_HEADER_ARCH_I386,
+            sizeof(multiboot2)
+        ),
+    },
+    .tag_none = {
+        .base = {
+            .type = KERNAUX_MULTIBOOT2_HTAG_NONE,
+            .flags = 0,
+            .size = sizeof(multiboot2.tag_none),
+        },
+    },
+};
+
+#include <kernaux/macro/packing_end.run>

src/start.S

@@ -1,21 +1,3 @@
-.set MULTIBOOT_MAGIC, 0xE85250D6
-.set MULTIBOOT_ARCH, 0
-.set MULTIBOOT_LENGTH, 16 + 8
-.set MULTIBOOT_CHECKSUM, -(MULTIBOOT_MAGIC + MULTIBOOT_ARCH + MULTIBOOT_LENGTH)
-
-
-
-.section .multiboot
-.align 4
-.long MULTIBOOT_MAGIC
-.long MULTIBOOT_ARCH
-.long MULTIBOOT_LENGTH
-.long MULTIBOOT_CHECKSUM
-.long 0
-.long 8
-
-
-
 .section .bss
 
 .global _kernel_stack_start