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 acbd2ee941be..de09a75557ab 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
@@ -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.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 7495efb6b14c..bd99495e5737 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
@@ -14,9 +14,11 @@
 // 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 e324b9382195..a8367876903a 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
@@ -14,9 +14,11 @@
 // 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 cdbf50263f16..5fbcc5ce753b 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
@@ -9,9 +9,11 @@
 // 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 2ac87e3abad5..63e797480b13 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
@@ -15,9 +15,11 @@
 // 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 93b65e2c79e3..d0d4b98aee46 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
@@ -8,9 +8,11 @@
 
 // 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 2fe7db3e98b1..d0990c0586b4 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
@@ -8,9 +8,11 @@
 
 // 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 ef9c36ed7bc9..fa8dc13cf649 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
@@ -9,9 +9,11 @@
 // 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