Index: clang/include/clang/Basic/AlignedAllocation.h
===================================================================
--- clang/include/clang/Basic/AlignedAllocation.h
+++ clang/include/clang/Basic/AlignedAllocation.h
@@ -27,8 +27,8 @@
   default:
     break;
   case llvm::Triple::Darwin:
-  case llvm::Triple::MacOSX: // Earliest supporting version is 10.13.
-    return llvm::VersionTuple(10U, 13U);
+  case llvm::Triple::MacOSX: // Earliest supporting version is 10.14.
+    return llvm::VersionTuple(10U, 14U);
   case llvm::Triple::IOS:
   case llvm::Triple::TvOS: // Earliest supporting version is 11.0.0.
     return llvm::VersionTuple(11U);
Index: clang/test/Driver/unavailable_aligned_allocation.cpp
===================================================================
--- clang/test/Driver/unavailable_aligned_allocation.cpp
+++ clang/test/Driver/unavailable_aligned_allocation.cpp
@@ -1,4 +1,4 @@
-// RUN: %clang -target x86_64-apple-macosx10.12 -c -### %s 2>&1 \
+// RUN: %clang -target x86_64-apple-macosx10.13 -c -### %s 2>&1 \
 // RUN:   | FileCheck %s -check-prefix=UNAVAILABLE
 //
 // RUN: %clang -target arm64-apple-ios10 -c -### %s 2>&1 \
@@ -24,7 +24,7 @@
 //
 // UNAVAILABLE: "-faligned-alloc-unavailable"
 
-// RUN: %clang -target x86_64-apple-macosx10.13 -c -### %s 2>&1 \
+// RUN: %clang -target x86_64-apple-macosx10.14 -c -### %s 2>&1 \
 // RUN:   | FileCheck %s -check-prefix=AVAILABLE
 //
 // RUN: %clang -target arm64-apple-ios11 -c -### %s 2>&1 \
@@ -54,10 +54,10 @@
 // Check that passing -faligned-allocation or -fno-aligned-allocation stops the
 // driver from passing -faligned-alloc-unavailable to cc1.
 //
-// RUN: %clang -target x86_64-apple-macosx10.12 -faligned-allocation -c -### %s 2>&1 \
+// RUN: %clang -target x86_64-apple-macosx10.13 -faligned-allocation -c -### %s 2>&1 \
 // RUN:   | FileCheck %s -check-prefix=AVAILABLE
 //
-// RUN: %clang -target x86_64-apple-macosx10.12 -fno-aligned-allocation -c -### %s 2>&1 \
+// RUN: %clang -target x86_64-apple-macosx10.13 -fno-aligned-allocation -c -### %s 2>&1 \
 // RUN:   | FileCheck %s -check-prefix=AVAILABLE
 
 // AVAILABLE-NOT: "-faligned-alloc-unavailable"
Index: clang/test/SemaCXX/unavailable_aligned_allocation.cpp
===================================================================
--- clang/test/SemaCXX/unavailable_aligned_allocation.cpp
+++ clang/test/SemaCXX/unavailable_aligned_allocation.cpp
@@ -1,6 +1,6 @@
-// RUN: %clang_cc1 -triple x86_64-apple-macosx10.12.0 -fexceptions -faligned-alloc-unavailable -std=c++1z -verify %s
-// RUN: %clang_cc1 -triple x86_64-apple-macosx10.12.0 -fexceptions -std=c++1z -verify -DNO_ERRORS %s
-// RUN: %clang_cc1 -triple x86_64-apple-macosx10.12.0 -fexceptions -faligned-allocation -faligned-alloc-unavailable -std=c++14 -verify %s
+// RUN: %clang_cc1 -triple x86_64-apple-macosx10.13.0 -fexceptions -faligned-alloc-unavailable -std=c++1z -verify %s
+// RUN: %clang_cc1 -triple x86_64-apple-macosx10.13.0 -fexceptions -std=c++1z -verify -DNO_ERRORS %s
+// RUN: %clang_cc1 -triple x86_64-apple-macosx10.13.0 -fexceptions -faligned-allocation -faligned-alloc-unavailable -std=c++14 -verify %s
 // RUN: %clang_cc1 -triple arm64-apple-ios10.0.0 -fexceptions -faligned-alloc-unavailable -std=c++1z -verify -DIOS %s
 // RUN: %clang_cc1 -triple arm64-apple-ios10.0.0 -fexceptions -std=c++1z -verify -DNO_ERRORS %s
 // RUN: %clang_cc1 -triple arm64-apple-tvos10.0.0 -fexceptions -faligned-alloc-unavailable -std=c++1z -verify -DTVOS %s
@@ -117,8 +117,8 @@
 // expected-error@-13 {{aligned allocation function of type 'void *(unsigned long, enum std::align_val_t)' is only available on watchOS 4 or newer}}}
 // expected-error@-14 {{aligned deallocation function of type 'void (void *, enum std::align_val_t) noexcept' is only available on watchOS 4 or newer}}}
 #else
-// expected-error@-16 {{aligned allocation function of type 'void *(unsigned long, enum std::align_val_t)' is only available on macOS 10.13 or newer}}}
-// expected-error@-17 {{aligned deallocation function of type 'void (void *, enum std::align_val_t) noexcept' is only available on macOS 10.13 or newer}}}
+// expected-error@-16 {{aligned allocation function of type 'void *(unsigned long, enum std::align_val_t)' is only available on macOS 10.14 or newer}}}
+// expected-error@-17 {{aligned deallocation function of type 'void (void *, enum std::align_val_t) noexcept' is only available on macOS 10.14 or newer}}}
 #endif
 
 // expected-note@-20 2 {{if you supply your own aligned allocation functions}}
@@ -146,7 +146,7 @@
 // expected-error@-12 {{aligned deallocation function of type 'void (void *, enum std::align_val_t) noexcept' is only available on watchOS 4 or newer}}}
 // expected-note@-13 {{if you supply your own aligned allocation functions}}
 #else
-// expected-error@-15 {{aligned deallocation function of type 'void (void *, enum std::align_val_t) noexcept' is only available on macOS 10.13 or newer}}}
+// expected-error@-15 {{aligned deallocation function of type 'void (void *, enum std::align_val_t) noexcept' is only available on macOS 10.14 or newer}}}
 // expected-note@-16 {{if you supply your own aligned allocation functions}}
 #endif
 #endif
Index: libcxx/test/libcxx/language.support/support.dynamic/libcpp_deallocate.sh.cpp
===================================================================
--- libcxx/test/libcxx/language.support/support.dynamic/libcpp_deallocate.sh.cpp
+++ libcxx/test/libcxx/language.support/support.dynamic/libcpp_deallocate.sh.cpp
@@ -14,9 +14,15 @@
 // definitions, which does not yet provide aligned allocation
 // XFAIL: LIBCXX-WINDOWS-FIXME
 
-// Clang 10 (and older) will trigger an availability error when the deployment
+// AppleClang 10 (and older) will trigger an availability error when the deployment
 // target does not support aligned allocation, even if we pass `-faligned-allocation`.
+// XFAIL: apple-clang-10 && availability=macosx10.13
 // XFAIL: apple-clang-10 && availability=macosx10.12
+// XFAIL: apple-clang-10 && availability=macosx10.11
+// XFAIL: apple-clang-10 && availability=macosx10.10
+// XFAIL: apple-clang-10 && availability=macosx10.9
+// XFAIL: apple-clang-10 && availability=macosx10.8
+// XFAIL: apple-clang-10 && availability=macosx10.7
 
 // The dylibs shipped before macosx10.14 do not contain the aligned allocation
 // functions, so trying to force using those with -faligned-allocation results
Index: libcxx/test/libcxx/memory/aligned_allocation_macro.pass.cpp
===================================================================
--- libcxx/test/libcxx/memory/aligned_allocation_macro.pass.cpp
+++ libcxx/test/libcxx/memory/aligned_allocation_macro.pass.cpp
@@ -9,8 +9,9 @@
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
 
-// Aligned allocation functions are not provided prior to macosx10.13, but
+// Aligned allocation functions are not provided prior to macosx10.14, but
 // AppleClang <= 10 does not know about this restriction and always enables them.
+// XFAIL: !(apple-clang-9 || apple-clang-10) && availability=macosx10.13
 // XFAIL: !(apple-clang-9 || apple-clang-10) && availability=macosx10.12
 // XFAIL: !(apple-clang-9 || apple-clang-10) && availability=macosx10.11
 // XFAIL: !(apple-clang-9 || apple-clang-10) && availability=macosx10.10