--- Libc/Libc-1725.40.4/gen/thread_stack_pcs.c
+++ Libc/Libc-1669.40.2/gen/thread_stack_pcs.c
@@ -26,15 +26,12 @@
 #include <pthread.h>
 #include <mach/mach.h>
 #include <mach/vm_statistics.h>
-#include <mach-o/dyld_priv.h>
 #include <stdlib.h>
 #include <pthread/private.h>
 #include <pthread/stack_np.h>
 #include "stack_logging.h"
 
-// maps regular stack to id=1 and dyld stack to id=2
-#define	STACKID(a)	(((a) >= stackbot && (a) <= stacktop) ? 1 : 2)
-#define	INSTACK(a)	(((a) >= stackbot && (a) <= stacktop) || (((a) != NULL) && (a) >= dyldstackbot && (a) <= dyldstacktop))
+#define	INSTACK(a)	((a) >= stackbot && (a) <= stacktop)
 #if defined(__x86_64__)
 #define	ISALIGNED(a)	((((uintptr_t)(a)) & 0xf) == 0)
 #elif defined(__i386__)
@@ -42,10 +39,6 @@
 #elif defined(__arm__) || defined(__arm64__)
 #define	ISALIGNED(a)	((((uintptr_t)(a)) & 0x1) == 0)
 #endif
-
-// If we're outside of the pthread stack, assume any frame larger than 1MB is a
-// bogus pointer and stop walking the stack
-#define MAX_ALT_FRAME_SIZE 0x100000
 
 // The Swift async ABI is not implemented on 32bit architectures.
 #if __LP64__ || __ARM64_ARCH_8_32__
@@ -139,8 +132,6 @@
 	pthread_t self = pthread_self();
 	void *stacktop = pthread_get_stackaddr_np(self);
 	void *stackbot = stacktop - pthread_get_stacksize_np(self);
-	const void *dyldstacktop = NULL;
-	const void *dyldstackbot = NULL;
 	unsigned int has_extended_frame = 0;
 	*nb = 0;
 
@@ -149,63 +140,11 @@
 	frame = __builtin_frame_address(0);
 	next = (void*)pthread_stack_frame_decode_np((uintptr_t)frame, NULL);
 
-	_dyld_stack_range(&dyldstackbot, &dyldstacktop);
-
-	if (!ISALIGNED(frame)) {
-		return 0;
-	} else if (!INSTACK(frame)) {
-		// Allow calls to thread_stack_pcs from one non-default stack to work
-		// around rdar://114874436
-		if (startfp || allow_async) {
-			return 0;
-		}
-		// Need to not decrement skip in the condition to avoid breaking to the
-		// rest of the function with an underflowed skip value
-		while (skip) {
-			skip--;
-			const ptrdiff_t diff = (ptrdiff_t)next - (ptrdiff_t)frame;
-			if (!ISALIGNED(next) || (!INSTACK(next) &&
-					(diff <= 0 || diff >= MAX_ALT_FRAME_SIZE))) {
-				return 0;
-			}
-			frame = next;
-			next = (void*)pthread_stack_frame_decode_np((uintptr_t)frame, NULL);
-			if (INSTACK(frame)) {
-				goto pthread_stacktrace;
-			}
-		}
-		while (max--) {
-			uintptr_t retaddr;
-#if __LP64__ || __ARM64_ARCH_8_32__
-			if (__is_async_frame((uintptr_t)frame)) {
-				has_extended_frame = 1;
-			}
-#endif
-			next = (void*)pthread_stack_frame_decode_np((uintptr_t)frame, &retaddr);
-			buffer[*nb] = retaddr;
-			(*nb)++;
-			const ptrdiff_t diff = (ptrdiff_t)next - (ptrdiff_t)frame;
-			if (!ISALIGNED(next) || (!INSTACK(next) &&
-					(diff <= 0 || diff >= MAX_ALT_FRAME_SIZE))) {
-				return has_extended_frame;
-			}
-			frame = next;
-			if (INSTACK(next)) {
-				break;
-			}
-		}
-		// We get to here either by jumping back to the pthread stack or by
-		// enumerating `max` frames in the non-default stack. In the latter
-		// case, we're now done
-		if (max + 1 == 0) {
-			return has_extended_frame;
-		}
-	}
-pthread_stacktrace:
-
 	/* make sure return address is never out of bounds */
 	stacktop -= (next - frame);
 
+	if(!INSTACK(frame) || !ISALIGNED(frame))
+		return 0;
 	while (startfp || skip--) {
 		if (startfp && startfp < next) break;
 		if(!INSTACK(next) || !ISALIGNED(next) || next <= frame)
@@ -230,7 +169,7 @@
 		next = (void*)pthread_stack_frame_decode_np((uintptr_t)frame, &retaddr);
 		buffer[*nb] = retaddr;
 		(*nb)++;
-		if(!INSTACK(next) || !ISALIGNED(next) || ((next <= frame) && (STACKID(next) == STACKID(frame))))
+		if(!INSTACK(next) || !ISALIGNED(next) || next <= frame)
 			return has_extended_frame;
 		frame = next;
 	}