Forward compatibility with future rename of _start to __start.

kernel/x64/boot.S

@@ -27,9 +27,12 @@
 .text 0x100000
 
 .global _start
+.global __start
 .type _start, @function
+.type __start, @function
 .code32
 _start:
+__start:
 	jmp prepare_kernel_execution
 
 	# Align 32 bits boundary.
@@ -148,6 +151,7 @@ Realm64:
 	# actual 64-bit kernel.
 	jmp Main
 .size _start, . - _start
+.size __start, . - __start
 
 .section .data
 GDT64:                           # Global Descriptor Table (64-bit).

kernel/x86/boot.S

@@ -27,8 +27,11 @@
 .text 0x100000
 
 .global _start
+.global __start
 .type _start, @function
+.type __start, @function
 _start:
+__start:
 	jmp prepare_kernel_execution
 
 	# Align 32 bits boundary.
@@ -66,3 +69,5 @@ prepare_kernel_execution:
 	fxsave fpu_initialized_regs
 
 	jmp beginkernel
+.size _start, . - _start
+.size __start, . - __start

libc/x64/crt0.S

@@ -26,8 +26,11 @@
 .section .text
 
 .global _start
+.global __start
 .type _start, @function
+.type __start, @function
 _start:
+__start:
 	# Set up end of the stack frame linked list.
 	xorl %ebp, %ebp
 	pushq %rbp # rip=0
@@ -57,3 +60,4 @@ _start:
 	movl %eax, %edi
 	call exit
 .size _start, .-_start
+.size __start, .-__start

libc/x86/crt0.S

@@ -26,8 +26,11 @@
 .section .text
 
 .global _start
+.global __start
 .type _start, @function
+.type __start, @function
 _start:
+__start:
 	# Set up end of the stack frame linked list.
 	xorl %ebp, %ebp
 	pushl %ebp # rip=0
@@ -61,3 +64,4 @@ _start:
 	push %eax
 	call exit
 .size _start, .-_start
+.size __start, .-__start