--- dyld/dyld-851.27/dyld3/APIs_macOS.cpp
+++ dyld/dyld-733.6/dyld3/APIs_macOS.cpp
@@ -38,10 +38,6 @@
 
 #include <algorithm>
 
-#if __has_feature(ptrauth_calls)
-  #include <ptrauth.h>
-#endif
-
 #include "dlfcn.h"
 
 #include "AllImages.h"
@@ -59,7 +55,7 @@
 
 
 // only in macOS and deprecated 
-#if TARGET_OS_OSX
+#if __MAC_OS_X_VERSION_MIN_REQUIRED
 
 // macOS needs to support an old API that only works with fileype==MH_BUNDLE.
 // In this deprecated API (unlike dlopen), loading and linking are separate steps.
@@ -74,7 +70,7 @@
 
     // verify path exists
      struct stat statbuf;
-    if ( dyld3::stat(path, &statbuf) == -1 )
+    if ( ::stat(path, &statbuf) == -1 )
         return NSObjectFileImageFailure;
 
     // create ofi that just contains path. NSLinkModule does all the work
@@ -102,13 +98,13 @@
     bool usable = false;
     const MachOFile* mf = (MachOFile*)memImage;
     if ( mf->hasMachOMagic() && mf->isMachO(diag, memImageSize) ) {
-        usable = (gAllImages.archs().grade(mf->cputype, mf->cpusubtype, false) != 0);
+        usable = (gAllImages.archs().grade(mf->cputype, mf->cpusubtype) != 0);
     }
     else if ( const FatFile* ff = FatFile::isFatFile(memImage) ) {
         uint64_t sliceOffset;
         uint64_t sliceLen;
         bool     missingSlice;
-        if ( ff->isFatFileWithSlice(diag, memImageSize, gAllImages.archs(), false, sliceOffset, sliceLen, missingSlice) ) {
+        if ( ff->isFatFileWithSlice(diag, memImageSize, gAllImages.archs(), sliceOffset, sliceLen, missingSlice) ) {
             mf = (MachOFile*)((long)memImage+sliceOffset);
             if ( mf->isMachO(diag, sliceLen) ) {
                 usable = true;
@@ -116,7 +112,7 @@
         }
     }
     if ( usable ) {
-        if ( !mf->builtForPlatform(Platform::macOS) )
+        if ( !mf->supportsPlatform(Platform::macOS) )
             usable = false;
     }
     if ( !usable ) {
@@ -347,15 +343,10 @@
 
 static bool flatFindSymbol(const char* symbolName, void** symbolAddress, const mach_header** foundInImageAtLoadAddress)
 {
-    // <rdar://problem/59265987> allow flat lookup to find "_memcpy" even though it is not implemented as that name in any dylib
-    MachOLoaded::DependentToMachOLoaded finder = ^(const MachOLoaded* mh, uint32_t depIndex) {
-        return gAllImages.findDependent(mh, depIndex);
-    };
-
     __block bool result = false;
     gAllImages.forEachImage(^(const LoadedImage& loadedImage, bool& stop) {
         bool resultPointsToInstructions = false;
-        if ( loadedImage.loadedAddress()->hasExportedSymbol(symbolName, finder, symbolAddress, &resultPointsToInstructions) ) {
+        if ( loadedImage.loadedAddress()->hasExportedSymbol(symbolName, nullptr, symbolAddress, &resultPointsToInstructions) ) {
             *foundInImageAtLoadAddress = loadedImage.loadedAddress();
             stop = true;
             result = true;
@@ -455,35 +446,8 @@
 {
     log_apis("NSAddressOfSymbol(%p)\n", symbol);
 
-	if ( symbol == nullptr )
-		return nullptr;
-
     // in dyld 1.0, NSSymbol was a pointer to the nlist entry in the symbol table
-    void *result = (void*)symbol;
-
-#if __has_feature(ptrauth_calls)
-    __block const MachOLoaded *module = nullptr;
-    gAllImages.infoForImageMappedAt(symbol, ^(const LoadedImage& foundImage, uint8_t permissions) {
-        module = foundImage.loadedAddress();
-    });
-
-    int64_t slide = module->getSlide();
-    __block bool resultPointsToInstructions = false;
-    module->forEachSection(^(const MachOAnalyzer::SectionInfo& sectInfo, bool malformedSectionRange, bool& stop) {
-        uint64_t sectStartAddr = sectInfo.sectAddr + slide;
-        uint64_t sectEndAddr = sectStartAddr + sectInfo.sectSize;
-        if ( ((uint64_t)result >= sectStartAddr) && ((uint64_t)result < sectEndAddr) ) {
-            resultPointsToInstructions = (sectInfo.sectFlags & S_ATTR_PURE_INSTRUCTIONS) || (sectInfo.sectFlags & S_ATTR_SOME_INSTRUCTIONS);
-            stop = true;
-        }
-    });
-
-    if (resultPointsToInstructions) {
-        result = __builtin_ptrauth_sign_unauthenticated(result, ptrauth_key_asia, 0);
-    }
-#endif
-
-    return result;
+    return (void*)symbol;
 }
 
 NSModule NSModuleForSymbol(NSSymbol symbol)