diff --git a/ape/loader-elf.S b/ape/loader-elf.S
index 8bf3fc507..5e2c3725c 100644
--- a/ape/loader-elf.S
+++ b/ape/loader-elf.S
@@ -222,7 +222,7 @@ _start:
 	cmp	$+1,%edx
 	jne	0f
 	mov	$XNU,%dl
-	mov	$0,%rcx
+	xor	%ecx,%ecx
 
 0:	mov	%rsp,%rsi
 	jmp	ApeLoader
diff --git a/ape/loader-macho.S b/ape/loader-macho.S
index 687603749..5bd2bbcd5 100644
--- a/ape/loader-macho.S
+++ b/ape/loader-macho.S
@@ -122,7 +122,7 @@ _start:
 	cmp	$+1,%edx
 	jne	0f
 	mov	$XNU,%dl
-	mov	$0,%rcx
+	xor	%ecx,%ecx
 
 0:	mov	%rsp,%rsi
 	jmp	ApeLoader
diff --git a/libc/crt/crt.S b/libc/crt/crt.S
index acff6d945..1cdca0e69 100644
--- a/libc/crt/crt.S
+++ b/libc/crt/crt.S
@@ -39,7 +39,7 @@ _start:
 	cmp	$+1,%edx
 	jne	0f
 	mov	$XNU,%cl
-	mov	$0,%rdi
+	xor	%edi,%edi
 0:
 #endif