Boot to C in 64-bit long mode

kernel/arch/x86_64/link.ld

@@ -0,0 +1,48 @@
+/* Nadir kernel linker script.
+ *
+ * Links the whole kernel (stage-2 entry + C code) as one flat binary loaded
+ * by the boot sector at 0x10000. Virtual addresses equal physical ones: the
+ * stage-2 page tables identity-map the first 1GB, so linked addresses work
+ * as-is the moment long mode is on.
+ *
+ * Layout rules: the stage-2 entry (.boot32) must be the very first bytes of
+ * the image, BSS exposes __bss_start/__bss_end for runtime zeroing, and
+ * toolchain metadata sections are discarded so the binary is pure code+data.
+ */
+
+ENTRY(boot32_entry)
+OUTPUT_ARCH(i386:x86-64)
+
+SECTIONS
+{
+    . = 0x10000;
+
+    .boot : {
+        *(.boot32)
+    }
+
+    .text : {
+        *(.text*)
+    }
+
+    .rodata : {
+        *(.rodata*)
+    }
+
+    .data : {
+        *(.data*)
+    }
+
+    .bss : {
+        __bss_start = .;
+        *(.bss*)
+        *(COMMON)
+        __bss_end = .;
+    }
+
+    /DISCARD/ : {
+        *(.note*)
+        *(.comment*)
+        *(.eh_frame*)
+    }
+}