diff --git a/clang/docs/LanguageExtensions.rst b/clang/docs/LanguageExtensions.rst
--- a/clang/docs/LanguageExtensions.rst
+++ b/clang/docs/LanguageExtensions.rst
@@ -2358,7 +2358,7 @@
 
 .. code-block:: c
 
-  const void * __builtin_preserve_access_index(const void * ptr)
+  void * __builtin_preserve_access_index(const volatile void * ptr)
 
 **Example of Use**:
 
diff --git a/clang/include/clang/Basic/Builtins.def b/clang/include/clang/Basic/Builtins.def
--- a/clang/include/clang/Basic/Builtins.def
+++ b/clang/include/clang/Basic/Builtins.def
@@ -1470,7 +1470,7 @@
 BUILTIN(__builtin_operator_delete, "vv*", "tn")
 BUILTIN(__builtin_char_memchr, "c*cC*iz", "n")
 BUILTIN(__builtin_dump_struct, "ivC*v*", "tn")
-BUILTIN(__builtin_preserve_access_index, "vC*vC*", "nU")
+BUILTIN(__builtin_preserve_access_index, "v*vCD*", "nU")
 
 // Safestack builtins
 BUILTIN(__builtin___get_unsafe_stack_start, "v*", "Fn")
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -1879,6 +1879,8 @@
 
     IsInPreservedAIRegion = true;
     Value *Res = EmitScalarExpr(E->getArg(0));
+    unsigned AddrSpace = Res->getType()->getPointerAddressSpace();
+    Res = Builder.CreateBitCast(Res, Int8Ty->getPointerTo(AddrSpace));
     IsInPreservedAIRegion = false;
     return RValue::get(Res);
   }
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -197,7 +197,6 @@
   if (checkArgCount(S, TheCall, 1))
     return true;
 
-  TheCall->setType(TheCall->getArg(0)->getType());
   return false;
 }
 
diff --git a/clang/test/Sema/builtin-preserve-access-index.c b/clang/test/Sema/builtin-preserve-access-index.c
--- a/clang/test/Sema/builtin-preserve-access-index.c
+++ b/clang/test/Sema/builtin-preserve-access-index.c
@@ -4,10 +4,10 @@
   return __builtin_preserve_access_index(&arg[1], 1); // expected-error {{too many arguments to function call, expected 1, have 2}}
 }
 
-void *invalid2(const int *arg) {
-  return __builtin_preserve_access_index(&arg[1]); // expected-warning {{returning 'const void *' from a function with result type 'void *' discards qualifiers}}
+void *valid2(const int *arg) {
+  return __builtin_preserve_access_index(&arg[1]);
 }
 
 const void *invalid3(const int *arg) {
-  return __builtin_preserve_access_index(1); // expected-warning {{incompatible integer to pointer conversion passing 'int' to parameter of type 'const void *'}}
+  return __builtin_preserve_access_index(1); // expected-warning {{incompatible integer to pointer conversion passing 'int' to parameter of type 'const volatile void *'}}
 }