Index: src/runtime/lookup-asm/lookup-asm-x86_64-elf.S
==================================================================
--- src/runtime/lookup-asm/lookup-asm-x86_64-elf.S
+++ src/runtime/lookup-asm/lookup-asm-x86_64-elf.S
@@ -30,10 +30,13 @@
 .macro generate_lookup name not_found
 \name:
 	test	rdi, rdi
 	jz	short ret_nil
 
+	bt	edi, 0
+	jc	short .Ltagged_pointer_\name
+
 	mov	r8, [rdi]
 	mov	r8, [r8+64]
 
 .Lmain_\name:
 	mov	rax, [rsi]
@@ -49,10 +52,20 @@
 
 	test	rax, rax
 	jz	short \not_found@PLT
 
 	ret
+
+.Ltagged_pointer_\name:
+	movzx	r8, dil
+	shr	r8, 1
+
+	mov	rax, [rip+objc_tagged_pointer_classes@GOTPCREL]
+	mov	r8, [rax+r8*8]
+	mov	r8, [r8+64]
+
+	jmp	short .Lmain_\name
 .type \name, %function
 .size \name, .-\name
 .endm
 
 .macro generate_lookup_super name lookup

Index: src/runtime/tagged-pointer.m
==================================================================
--- src/runtime/tagged-pointer.m
+++ src/runtime/tagged-pointer.m
@@ -19,11 +19,11 @@
 
 #import "private.h"
 
 #define NUM_TAGGED_POINTER_CLASSES 0x7F
 
-static Class taggedPointerClasses[NUM_TAGGED_POINTER_CLASSES];
+Class objc_tagged_pointer_classes[NUM_TAGGED_POINTER_CLASSES];
 static uint_fast8_t taggedPointerClassesCount;
 
 int_fast8_t
 objc_registerTaggedPointerClass(Class class)
 {
@@ -35,11 +35,11 @@
 		objc_global_mutex_unlock();
 		return -1;
 	}
 
 	i = taggedPointerClassesCount++;
-	taggedPointerClasses[i] = class;
+	objc_tagged_pointer_classes[i] = class;
 
 	objc_global_mutex_unlock();
 
 	return i;
 }
@@ -53,11 +53,11 @@
 	pointer >>= 1;
 
 	if (pointer >= NUM_TAGGED_POINTER_CLASSES)
 		return Nil;
 
-	return taggedPointerClasses[pointer];
+	return objc_tagged_pointer_classes[pointer];
 }
 
 uintptr_t
 object_getTaggedPointerValue(id object)
 {