Index: clang/include/clang/Basic/CodeGenOptions.def
===================================================================
--- clang/include/clang/Basic/CodeGenOptions.def
+++ clang/include/clang/Basic/CodeGenOptions.def
@@ -469,6 +469,9 @@
 ENUM_CODEGENOPT(ZeroCallUsedRegs, llvm::ZeroCallUsedRegs::ZeroCallUsedRegsKind,
                 5, llvm::ZeroCallUsedRegs::ZeroCallUsedRegsKind::Skip)
 
+/// Whether to use opaque pointers.
+CODEGENOPT(OpaquePointers, 1, 0)
+
 #undef CODEGENOPT
 #undef ENUM_CODEGENOPT
 #undef VALUE_CODEGENOPT
Index: clang/include/clang/Driver/Options.td
===================================================================
--- clang/include/clang/Driver/Options.td
+++ clang/include/clang/Driver/Options.td
@@ -5504,6 +5504,13 @@
   PosFlag<SetTrue, [], "Enable">,
   NegFlag<SetFalse, [], "Disable">,
   BothFlags<[], " analyzing function argument and return types for mandatory definedness">>;
+defm opaque_pointers : BoolOption<"",
+  "opaque-pointers",
+  CodeGenOpts<"OpaquePointers">,
+  DefaultFalse,
+  PosFlag<SetTrue, [], "Enable">,
+  NegFlag<SetFalse, [], "Disable">,
+  BothFlags<[], " opaque pointers">>;
 def discard_value_names : Flag<["-"], "discard-value-names">,
   HelpText<"Discard value names in LLVM IR">,
   MarshallingInfoFlag<CodeGenOpts<"DiscardValueNames">>;
Index: clang/lib/CodeGen/CodeGenAction.cpp
===================================================================
--- clang/lib/CodeGen/CodeGenAction.cpp
+++ clang/lib/CodeGen/CodeGenAction.cpp
@@ -983,6 +983,9 @@
   if (BA != Backend_EmitNothing && !OS)
     return nullptr;
 
+  if (CI.getCodeGenOpts().OpaquePointers)
+    VMContext->enableOpaquePointers();
+
   // Load bitcode modules to link with, if we need to.
   if (LinkModules.empty())
     for (const CodeGenOptions::BitcodeFileToLink &F :
Index: clang/test/CodeGen/opaque-pointers-flag.c
===================================================================
--- /dev/null
+++ clang/test/CodeGen/opaque-pointers-flag.c
@@ -0,0 +1,27 @@
+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py
+// RUN: %clang_cc1 -no-opaque-pointers -triple x86_64-unknown-unknown -emit-llvm %s -o - | FileCheck %s -check-prefix=TYPED
+// RUN: %clang_cc1 -opaque-pointers -triple x86_64-unknown-unknown -emit-llvm %s -o - | FileCheck %s -check-prefix=OPAQUE
+// The current default is typed pointers:
+// RUN: %clang_cc1 -triple x86_64-unknown-unknown -emit-llvm %s -o - | FileCheck %s -check-prefix=TYPED
+
+// TYPED-LABEL: @test(
+// TYPED-NEXT:  entry:
+// TYPED-NEXT:    [[P_ADDR:%.*]] = alloca i32*, align 8
+// TYPED-NEXT:    store i32* [[P:%.*]], i32** [[P_ADDR]], align 8
+// TYPED-NEXT:    [[TMP0:%.*]] = load i32*, i32** [[P_ADDR]], align 8
+// TYPED-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i32, i32* [[TMP0]], i64 1
+// TYPED-NEXT:    [[TMP1:%.*]] = load i32, i32* [[ARRAYIDX]], align 4
+// TYPED-NEXT:    ret i32 [[TMP1]]
+//
+// OPAQUE-LABEL: @test(
+// OPAQUE-NEXT:  entry:
+// OPAQUE-NEXT:    [[P_ADDR:%.*]] = alloca ptr, align 8
+// OPAQUE-NEXT:    store ptr [[P:%.*]], ptr [[P_ADDR]], align 8
+// OPAQUE-NEXT:    [[TMP0:%.*]] = load ptr, ptr [[P_ADDR]], align 8
+// OPAQUE-NEXT:    [[ARRAYIDX:%.*]] = getelementptr inbounds i32, ptr [[TMP0]], i64 1
+// OPAQUE-NEXT:    [[TMP1:%.*]] = load i32, ptr [[ARRAYIDX]], align 4
+// OPAQUE-NEXT:    ret i32 [[TMP1]]
+//
+int test(int *p) {
+  return p[1];
+}