diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/delete_align_val_t_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/delete_align_val_t_replace.pass.cpp
index 4dd9390c4fdcf..bd20e090637d0 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/delete_align_val_t_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/delete_align_val_t_replace.pass.cpp
@@ -17,9 +17,11 @@
 // None of the current GCC compilers support this.
 // UNSUPPORTED: gcc-5, gcc-6
 
-// Aligned allocation was not provided before macosx10.12 and as a result we
-// get availability errors when the deployment target is older than macosx10.13.
-// However, AppleClang 10 (and older) don't trigger availability errors.
+// Aligned allocation was not provided before macosx10.14 and as a result we
+// get availability errors when the deployment target is older than macosx10.14.
+// However, AppleClang 10 (and older) don't trigger availability errors, and
+// Clang < 8.0 doesn't warn for 10.13.
+// XFAIL: !(apple-clang-9 || apple-clang-10 || clang-7) && 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
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t.pass.cpp
index d6194b00aa025..6b4e1c1924b4a 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t.pass.cpp
@@ -15,9 +15,11 @@
 // FIXME change this to XFAIL.
 // UNSUPPORTED: no-aligned-allocation && !gcc
 
-// Aligned allocation was not provided before macosx10.12 and as a result we
-// get availability errors when the deployment target is older than macosx10.13.
-// However, AppleClang 10 (and older) don't trigger availability errors.
+// Aligned allocation was not provided before macosx10.14 and as a result we
+// get availability errors when the deployment target is older than macosx10.14.
+// However, AppleClang 10 (and older) don't trigger availability errors, and
+// Clang < 8.0 doesn't warn for 10.13.
+// XFAIL: !(apple-clang-9 || apple-clang-10 || clang-7) && 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
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow.pass.cpp
index 59878aefd18a2..3188cc587dde9 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow.pass.cpp
@@ -15,9 +15,11 @@
 // FIXME turn this into an XFAIL
 // UNSUPPORTED: no-aligned-allocation && !gcc
 
-// Aligned allocation was not provided before macosx10.12 and as a result we
-// get availability errors when the deployment target is older than macosx10.13.
-// However, AppleClang 10 (and older) don't trigger availability errors.
+// Aligned allocation was not provided before macosx10.14 and as a result we
+// get availability errors when the deployment target is older than macosx10.14.
+// However, AppleClang 10 (and older) don't trigger availability errors, and
+// Clang < 8.0 doesn't warn for 10.13.
+// XFAIL: !(apple-clang-9 || apple-clang-10 || clang-7) && 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
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow_replace.pass.cpp
index fc713dbf8ed83..29d8fd06a701e 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.array/new_align_val_t_nothrow_replace.pass.cpp
@@ -10,9 +10,11 @@
 // UNSUPPORTED: c++98, c++03, c++11, c++14
 // UNSUPPORTED: sanitizer-new-delete
 
-// Aligned allocation was not provided before macosx10.12 and as a result we
-// get availability errors when the deployment target is older than macosx10.13.
-// However, AppleClang 10 (and older) don't trigger availability errors.
+// Aligned allocation was not provided before macosx10.14 and as a result we
+// get availability errors when the deployment target is older than macosx10.14.
+// However, AppleClang 10 (and older) don't trigger availability errors, and
+// Clang < 8.0 doesn't warn for 10.13.
+// XFAIL: !(apple-clang-9 || apple-clang-10 || clang-7) && 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
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/delete_align_val_t_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/delete_align_val_t_replace.pass.cpp
index 19cabcce1edd9..c01e39915ec01 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/delete_align_val_t_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/delete_align_val_t_replace.pass.cpp
@@ -16,9 +16,11 @@
 // None of the current GCC compilers support this.
 // UNSUPPORTED: gcc-5, gcc-6
 
-// Aligned allocation was not provided before macosx10.12 and as a result we
-// get availability errors when the deployment target is older than macosx10.13.
-// However, AppleClang 10 (and older) don't trigger availability errors.
+// Aligned allocation was not provided before macosx10.14 and as a result we
+// get availability errors when the deployment target is older than macosx10.14.
+// However, AppleClang 10 (and older) don't trigger availability errors, and
+// Clang < 8.0 doesn't warn for 10.13
+// XFAIL: !(apple-clang-9 || apple-clang-10 || clang-7) && 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
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t.pass.cpp
index 7cf1aca3b9f8e..8cb40885c466f 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t.pass.cpp
@@ -9,9 +9,11 @@
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
 
-// Aligned allocation was not provided before macosx10.12 and as a result we
-// get availability errors when the deployment target is older than macosx10.13.
-// However, AppleClang 10 (and older) don't trigger availability errors.
+// Aligned allocation was not provided before macosx10.14 and as a result we
+// get availability errors when the deployment target is older than macosx10.14.
+// However, AppleClang 10 (and older) don't trigger availability errors, and
+// Clang < 8.0 doesn't warn for 10.13.
+// XFAIL: !(apple-clang-9 || apple-clang-10 || clang-7) && 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
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow.pass.cpp
index dd2666e00aad4..9d7f13bee3288 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow.pass.cpp
@@ -9,9 +9,11 @@
 
 // UNSUPPORTED: c++98, c++03, c++11, c++14
 
-// Aligned allocation was not provided before macosx10.12 and as a result we
-// get availability errors when the deployment target is older than macosx10.13.
-// However, AppleClang 10 (and older) don't trigger availability errors.
+// Aligned allocation was not provided before macosx10.14 and as a result we
+// get availability errors when the deployment target is older than macosx10.14.
+// However, AppleClang 10 (and older) don't trigger availability errors, and
+// Clang < 8.0 doesn't warn for 10.13
+// XFAIL: !(apple-clang-9 || apple-clang-10 || clang-7) && 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
diff --git a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow_replace.pass.cpp b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow_replace.pass.cpp
index 514a2b8afc8c3..82367d7de093b 100644
--- a/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow_replace.pass.cpp
+++ b/libcxx/test/std/language.support/support.dynamic/new.delete/new.delete.single/new_align_val_t_nothrow_replace.pass.cpp
@@ -10,9 +10,11 @@
 // UNSUPPORTED: c++98, c++03, c++11, c++14
 // UNSUPPORTED: sanitizer-new-delete
 
-// Aligned allocation was not provided before macosx10.12 and as a result we
-// get availability errors when the deployment target is older than macosx10.13.
-// However, AppleClang 10 (and older) don't trigger availability errors.
+// Aligned allocation was not provided before macosx10.14 and as a result we
+// get availability errors when the deployment target is older than macosx10.14.
+// However, AppleClang 10 (and older) don't trigger availability errors, and
+// Clang < 8.0 doesn't warn for 10.13
+// XFAIL: !(apple-clang-9 || apple-clang-10 || clang-7) && 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