diff --git a/clang/test/CodeGen/asan-globals-odr.cpp b/clang/test/CodeGen/asan-globals-odr.cpp
--- a/clang/test/CodeGen/asan-globals-odr.cpp
+++ b/clang/test/CodeGen/asan-globals-odr.cpp
@@ -1,8 +1,8 @@
-// RUN: %clang_cc1 -fsanitize=address -emit-llvm -o - -triple x86_64-linux %s | FileCheck %s --check-prefixes=CHECK,INDICATOR0,GLOB_VAR,ALIAS0
+// RUN: %clang_cc1 -fsanitize=address -emit-llvm -o - -triple x86_64-linux %s | FileCheck %s --check-prefixes=CHECK,INDICATOR0,GLOB_ALIAS,ALIAS1
 // RUN: %clang_cc1 -fsanitize=address -fsanitize-address-use-odr-indicator -emit-llvm -o - -triple x86_64-linux %s | FileCheck %s --check-prefixes=CHECK,INDICATOR1,GLOB_ALIAS_INDICATOR,ALIAS1
-// RUN: %clang_cc1 -fsanitize=address -fno-sanitize-address-use-odr-indicator -emit-llvm -o - -triple x86_64-linux %s | FileCheck %s --check-prefixes=CHECK,INDICATOR0,GLOB_VAR,ALIAS0
+// RUN: %clang_cc1 -fsanitize=address -fno-sanitize-address-use-odr-indicator -emit-llvm -o - -triple x86_64-linux %s | FileCheck %s --check-prefixes=CHECK,INDICATOR0,GLOB_ALIAS,ALIAS1
 // RUN: %clang_cc1 -fsanitize=address -fno-sanitize-address-use-odr-indicator -fsanitize-address-use-odr-indicator -emit-llvm -o - -triple x86_64-linux %s | FileCheck %s --check-prefixes=CHECK,INDICATOR1,GLOB_ALIAS_INDICATOR,ALIAS1
-// RUN: %clang_cc1 -fsanitize=address -fsanitize-address-use-odr-indicator -fno-sanitize-address-use-odr-indicator -emit-llvm -o - -triple x86_64-linux %s | FileCheck %s --check-prefixes=CHECK,INDICATOR0,GLOB_VAR,ALIAS0
+// RUN: %clang_cc1 -fsanitize=address -fsanitize-address-use-odr-indicator -fno-sanitize-address-use-odr-indicator -emit-llvm -o - -triple x86_64-linux %s | FileCheck %s --check-prefixes=CHECK,INDICATOR0,GLOB_ALIAS,ALIAS1
 
 // No alias on Windows but indicators should work.
 // RUN: %clang_cc1 -fsanitize=address -emit-llvm -o - -triple x86_64-windows-msvc %s | FileCheck %s --check-prefixes=CHECK,GLOB_VAR,ALIAS0
diff --git a/clang/test/CodeGen/asan-static-odr.cpp b/clang/test/CodeGen/asan-static-odr.cpp
--- a/clang/test/CodeGen/asan-static-odr.cpp
+++ b/clang/test/CodeGen/asan-static-odr.cpp
@@ -1,7 +1,7 @@
-// RUN: %clang_cc1 -fsanitize=address -emit-llvm -o - -triple x86_64-linux %s | FileCheck %s
+// RUN: %clang_cc1 -fsanitize=address -emit-llvm -o - -triple x86_64-linux %s | FileCheck %s --check-prefixes=CHECK,ELF
 
 // No alias on Windows but indicators should work.
-// RUN: %clang_cc1 -fsanitize=address -emit-llvm -o - -triple x86_64-windows-msvc %s | FileCheck %s
+// RUN: %clang_cc1 -fsanitize=address -emit-llvm -o - -triple x86_64-windows-msvc %s | FileCheck %s --check-prefixes=CHECK,COFF
 
 static int global;
 
@@ -12,6 +12,9 @@
 // CHECK-NOT: __odr_asan_gen
 // CHECK-NOT: private alias
 // CHECK: [[VAR:@.*global.*]] ={{.*}} global { i32, [60 x i8] } zeroinitializer, align 32
-// CHECK: @0 = internal global {{.*}} [[VAR]] to i64), {{.*}}, i64 -1 }]
+// ELF:   @0 = internal global {{.*}} @1 to i64), {{.*}}, i64 -1 }]
+// ELF:   @1 = private alias { i32, [60 x i8] }, { i32, [60 x i8] }* [[VAR]]
+// WIN:   @0 = internal global {{.*}} [[VAR]] to i64), {{.*}}, i64 -1 }]
+// WIN-NOT: private alias
 // CHECK: call void @__asan_register_globals(i64 ptrtoint ([1 x { i64, i64, i64, i64, i64, i64, i64, i64 }]* @0 to i64), i64 1)
 // CHECK: call void @__asan_unregister_globals(i64 ptrtoint ([1 x { i64, i64, i64, i64, i64, i64, i64, i64 }]* @0 to i64), i64 1)
diff --git a/compiler-rt/test/asan/TestCases/Linux/odr-violation.cpp b/compiler-rt/test/asan/TestCases/Linux/odr-violation.cpp
--- a/compiler-rt/test/asan/TestCases/Linux/odr-violation.cpp
+++ b/compiler-rt/test/asan/TestCases/Linux/odr-violation.cpp
@@ -6,16 +6,18 @@
 // We use fast_unwind_on_malloc=0 to have full unwinding even w/o frame
 // pointers. This setting is not on by default because it's too expensive.
 //
+// Note, -asan-use-private-alias=1 -asan-use-odr-indicator=0 is the default.
+//
 // Different size: detect a bug if detect_odr_violation>=1
-// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared %s -o %dynamiclib
-// RUN: %clangxx_asan %s %ld_flags_rpath_exe -o %t-ODR-EXE
+// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared -mllvm -asan-use-private-alias=0 %s -o %dynamiclib
+// RUN: %clangxx_asan -mllvm -asan-use-private-alias=0 %s %ld_flags_rpath_exe -o %t-ODR-EXE
 // RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=1 not %run %t-ODR-EXE 2>&1 | FileCheck %s
 // RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=2 not %run %t-ODR-EXE 2>&1 | FileCheck %s
 // RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=0     %run %t-ODR-EXE 2>&1 | FileCheck %s --check-prefix=DISABLED
 // RUN: %env_asan_opts=fast_unwind_on_malloc=0                        not %run %t-ODR-EXE 2>&1 | FileCheck %s
 //
 // Same size: report a bug only if detect_odr_violation>=2.
-// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared %s -o %dynamiclib -DSZ=100
+// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared -mllvm -asan-use-private-alias=0 %s -o %dynamiclib -DSZ=100
 // RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=1     %run %t-ODR-EXE 2>&1 | FileCheck %s --check-prefix=DISABLED
 // RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=2 not %run %t-ODR-EXE 2>&1 | FileCheck %s
 // RUN: %env_asan_opts=fast_unwind_on_malloc=0                        not %run %t-ODR-EXE 2>&1 | FileCheck %s
@@ -26,12 +28,12 @@
 // RUN: rm -f %t.supp
 //
 // Use private aliases for global variables without indicator symbol.
-// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared -mllvm -asan-use-private-alias %s -o %dynamiclib -DSZ=100
+// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared %s -o %dynamiclib -DSZ=100
 // RUN: %clangxx_asan -mllvm -asan-use-private-alias %s %ld_flags_rpath_exe -o %t-ODR-EXE
 // RUN: %env_asan_opts=fast_unwind_on_malloc=0 %run %t-ODR-EXE 2>&1 | FileCheck %s --check-prefix=DISABLED
 
 // Use private aliases for global variables: use indicator symbol to detect ODR violation.
-// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared -mllvm -asan-use-private-alias -mllvm -asan-use-odr-indicator  %s -o %dynamiclib -DSZ=100
+// RUN: %clangxx_asan -DBUILD_SO=1 -fPIC -shared -mllvm -asan-use-odr-indicator  %s -o %dynamiclib -DSZ=100
 // RUN: %clangxx_asan -mllvm -asan-use-private-alias -mllvm -asan-use-odr-indicator %s %ld_flags_rpath_exe -o %t-ODR-EXE
 // RUN: %env_asan_opts=fast_unwind_on_malloc=0 not %run %t-ODR-EXE 2>&1 | FileCheck %s
 
diff --git a/compiler-rt/test/asan/TestCases/Linux/odr-vtable.cpp b/compiler-rt/test/asan/TestCases/Linux/odr-vtable.cpp
--- a/compiler-rt/test/asan/TestCases/Linux/odr-vtable.cpp
+++ b/compiler-rt/test/asan/TestCases/Linux/odr-vtable.cpp
@@ -1,9 +1,19 @@
 // Fails with debug checks: https://bugs.llvm.org/show_bug.cgi?id=46862
 // XFAIL: !compiler-rt-optimized && !riscv64
 
+/// By default we cannot detect ODR issues in vtables.
 // RUN: %clangxx_asan -fno-rtti -DBUILD_SO1 -fPIC -shared %s -o %dynamiclib1
 // RUN: %clangxx_asan -fno-rtti -DBUILD_SO2 -fPIC -shared %s -o %dynamiclib2
 // RUN: %clangxx_asan -fno-rtti %s %ld_flags_rpath_exe1 %ld_flags_rpath_exe2 -o %t
+// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=2 %run %t 2>&1 | count 0
+
+/// Not using private alias or enabling ODR indicator can detect ODR issues.
+// RUN: %clangxx_asan -fno-rtti -DBUILD_SO1 -fPIC -shared -mllvm -asan-use-private-alias=0 %s -o %dynamiclib1
+// RUN: %clangxx_asan -fno-rtti -DBUILD_SO2 -fPIC -shared -mllvm -asan-use-private-alias=0 %s -o %dynamiclib2
+// RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=2 not %run %t 2>&1 | FileCheck %s
+
+// RUN: %clangxx_asan -fno-rtti -DBUILD_SO1 -fPIC -shared -mllvm -asan-use-odr-indicator=1 %s -o %dynamiclib1
+// RUN: %clangxx_asan -fno-rtti -DBUILD_SO2 -fPIC -shared -mllvm -asan-use-odr-indicator=1 %s -o %dynamiclib2
 // RUN: %env_asan_opts=fast_unwind_on_malloc=0:detect_odr_violation=2 not %run %t 2>&1 | FileCheck %s
 
 struct XYZ {
diff --git a/compiler-rt/test/asan/TestCases/Linux/odr_c_test.c b/compiler-rt/test/asan/TestCases/Linux/odr_c_test.c
--- a/compiler-rt/test/asan/TestCases/Linux/odr_c_test.c
+++ b/compiler-rt/test/asan/TestCases/Linux/odr_c_test.c
@@ -1,8 +1,8 @@
-// Test that we can properly report an ODR violation
-// between an instrumented global and a non-instrumented global.
+// Test that we can properly report an ODR violation between an instrumented
+// global and a non-instrumented global if not using private aliases.
 
-// RUN: %clang_asan -fcommon %s -fPIC -shared -o %dynamiclib1  -DFILE1
-// RUN: %clang_asan -fcommon %s -fPIC -shared -o %dynamiclib2  -DFILE2
+// RUN: %clang_asan -fcommon %s -fPIC -shared -mllvm -asan-use-private-alias=0 -o %dynamiclib1  -DFILE1
+// RUN: %clang_asan -fcommon %s -fPIC -shared -mllvm -asan-use-private-alias=0 -o %dynamiclib2  -DFILE2
 // RUN: %clang_asan -fcommon %s -fPIE %ld_flags_rpath_exe1 %ld_flags_rpath_exe2 -o %t
 // RUN: not %run %t 2>&1 | FileCheck %s
 //
diff --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -363,7 +363,7 @@
 static cl::opt<bool>
     ClUsePrivateAlias("asan-use-private-alias",
                       cl::desc("Use private aliases for global variables"),
-                      cl::Hidden, cl::init(false));
+                      cl::Hidden, cl::init(true));
 
 static cl::opt<bool>
     ClUseOdrIndicator("asan-use-odr-indicator",
diff --git a/llvm/test/Instrumentation/AddressSanitizer/global_metadata.ll b/llvm/test/Instrumentation/AddressSanitizer/global_metadata.ll
--- a/llvm/test/Instrumentation/AddressSanitizer/global_metadata.ll
+++ b/llvm/test/Instrumentation/AddressSanitizer/global_metadata.ll
@@ -1,7 +1,7 @@
-; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-globals-live-support=1 -S | FileCheck %s
-; RUN: opt < %s -passes='asan-pipeline' -asan-globals-live-support=1 -S | FileCheck %s
-; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-globals-live-support=1 -asan-mapping-scale=5 -S | FileCheck %s
-; RUN: opt < %s -passes='asan-pipeline' -asan-globals-live-support=1 -asan-mapping-scale=5 -S | FileCheck %s
+; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-private-alias=0 -asan-globals-live-support=1 -S | FileCheck %s
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-private-alias=0 -asan-globals-live-support=1 -S | FileCheck %s
+; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-private-alias=0 -asan-globals-live-support=1 -asan-mapping-scale=5 -S | FileCheck %s
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-private-alias=0 -asan-globals-live-support=1 -asan-mapping-scale=5 -S | FileCheck %s
 
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"
diff --git a/llvm/test/Instrumentation/AddressSanitizer/global_metadata_darwin.ll b/llvm/test/Instrumentation/AddressSanitizer/global_metadata_darwin.ll
--- a/llvm/test/Instrumentation/AddressSanitizer/global_metadata_darwin.ll
+++ b/llvm/test/Instrumentation/AddressSanitizer/global_metadata_darwin.ll
@@ -2,8 +2,8 @@
 ; allowing dead stripping to be performed, and that the appropriate runtime
 ; routines are invoked.
 
-; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-globals-live-support=1 -S | FileCheck %s
-; RUN: opt < %s -passes='asan-pipeline' -asan-globals-live-support=1 -S | FileCheck %s
+; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-private-alias=0 -asan-globals-live-support=1 -S | FileCheck %s
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-private-alias=0 -asan-globals-live-support=1 -S | FileCheck %s
 
 target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-apple-macosx10.11.0"
diff --git a/llvm/test/Instrumentation/AddressSanitizer/local_alias.ll b/llvm/test/Instrumentation/AddressSanitizer/local_alias.ll
--- a/llvm/test/Instrumentation/AddressSanitizer/local_alias.ll
+++ b/llvm/test/Instrumentation/AddressSanitizer/local_alias.ll
@@ -1,11 +1,11 @@
-; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -S | FileCheck %s --check-prefixes=CHECK-NOALIAS,CHECK-NOINDICATOR
-; RUN: opt < %s -passes='asan-pipeline' -S | FileCheck %s --check-prefixes=CHECK-NOALIAS,CHECK-NOINDICATOR
+; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -S | FileCheck %s --check-prefixes=CHECK-ALIAS,CHECK-NOINDICATOR
+; RUN: opt < %s -passes='asan-pipeline' -S | FileCheck %s --check-prefixes=CHECK-ALIAS,CHECK-NOINDICATOR
 ; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-private-alias=1 -S | FileCheck %s --check-prefixes=CHECK-ALIAS,CHECK-NOINDICATOR
-; RUN: opt < %s -passes='asan-pipeline' -asan-use-private-alias=1 -S | FileCheck %s --check-prefixes=CHECK-ALIAS,CHECK-NOINDICATOR
-; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-odr-indicator=1 -S | FileCheck %s --check-prefixes=CHECK-INDICATOR,CHECK-NOALIAS
-; RUN: opt < %s -passes='asan-pipeline' -asan-use-odr-indicator=1 -S | FileCheck %s --check-prefixes=CHECK-INDICATOR,CHECK-NOALIAS
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-private-alias=0 -S | FileCheck %s --check-prefixes=CHECK-NOALIAS,CHECK-NOINDICATOR
+; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-odr-indicator=1 -S | FileCheck %s --check-prefixes=CHECK-INDICATOR,CHECK-ALIAS
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-odr-indicator=1 -S | FileCheck %s --check-prefixes=CHECK-INDICATOR,CHECK-ALIAS
 ; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -asan-use-private-alias=1 -asan-use-odr-indicator=1 -S | FileCheck %s --check-prefixes=CHECK-ALIAS,CHECK-INDICATOR
-; RUN: opt < %s -passes='asan-pipeline' -asan-use-private-alias=1 -asan-use-odr-indicator=1 -S | FileCheck %s --check-prefixes=CHECK-ALIAS,CHECK-INDICATOR
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-private-alias=0 -asan-use-odr-indicator=1 -S | FileCheck %s --check-prefixes=CHECK-NOALIAS,CHECK-INDICATOR
 
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"
diff --git a/llvm/test/Instrumentation/AddressSanitizer/odr-check-ignore.ll b/llvm/test/Instrumentation/AddressSanitizer/odr-check-ignore.ll
--- a/llvm/test/Instrumentation/AddressSanitizer/odr-check-ignore.ll
+++ b/llvm/test/Instrumentation/AddressSanitizer/odr-check-ignore.ll
@@ -1,5 +1,5 @@
-; RUN: opt < %s -asan -asan-module -enable-new-pm=0 -S | FileCheck %s 
-; RUN: opt < %s -passes='asan-pipeline' -S | FileCheck %s 
+; RUN: opt < %s -asan -asan-module -asan-use-private-alias=0 -enable-new-pm=0 -S | FileCheck %s
+; RUN: opt < %s -passes='asan-pipeline' -asan-use-private-alias=0 -S | FileCheck %s
 
 target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
 target triple = "x86_64-unknown-linux-gnu"