diff --git a/test/Feature/CBuffer/arrays-16bit.test b/test/Feature/CBuffer/arrays-16bit.test
index 56128961..67dc11d6 100644
--- a/test/Feature/CBuffer/arrays-16bit.test
+++ b/test/Feature/CBuffer/arrays-16bit.test
@@ -59,7 +59,7 @@ DescriptorSets:
 # DXC's vulkan support does not layout cbuffers compatibly with DXIL
 # UNSUPPORTED: Vulkan
 
-# https://github.com/llvm/llvm-project/issues/110722
+# https://github.com/llvm/llvm-project/issues/138996
 # XFAIL: Clang
 
 # RUN: split-file %s %t
diff --git a/test/Feature/CBuffer/lit.local.cfg b/test/Feature/CBuffer/lit.local.cfg
index 581c118e..1d8227d6 100644
--- a/test/Feature/CBuffer/lit.local.cfg
+++ b/test/Feature/CBuffer/lit.local.cfg
@@ -1,4 +1,4 @@
-if 'Clang' in config.available_features:
+if 'Clang-Vulkan' in config.available_features:
     config.unsupported = True
 
 # CBuffer bindings seem to be broken under metal
diff --git a/test/Feature/CBuffer/structs.test b/test/Feature/CBuffer/structs.test
index 09c47c0e..4b48956e 100644
--- a/test/Feature/CBuffer/structs.test
+++ b/test/Feature/CBuffer/structs.test
@@ -97,6 +97,10 @@ DescriptorSets:
 # DXC's vulkan support does not layout cbuffers compatibly with DXIL
 # UNSUPPORTED: Vulkan
 
++# Clang trips on 2-element vectors in structs:
++# https://github.com/llvm/llvm-project/issues/123968
++# XFAIL: Clang
+
 # RUN: split-file %s %t
 # RUN: %dxc_target -T cs_6_5 -Fo %t.o %t/source.hlsl
 # RUN: %offloader %t/pipeline.yaml %t.o | FileCheck %s
diff --git a/test/Feature/CBuffer/vectors-64bit.test b/test/Feature/CBuffer/vectors-64bit.test
index b074fefd..701dfcfe 100644
--- a/test/Feature/CBuffer/vectors-64bit.test
+++ b/test/Feature/CBuffer/vectors-64bit.test
@@ -63,6 +63,10 @@ DescriptorSets:
 # DXC's vulkan support does not layout cbuffers compatibly with DXIL
 # UNSUPPORTED: Vulkan
 
+# Clang trips on 3-element vectors in structs:
+# https://github.com/llvm/llvm-project/issues/123968
+# XFAIL: Clang
+
 # RUN: split-file %s %t
 # RUN: %dxc_target -T cs_6_5 -Fo %t.o %t/source.hlsl
 # RUN: %offloader %t/pipeline.yaml %t.o | FileCheck %s
diff --git a/test/Feature/CBuffer/vectors.test b/test/Feature/CBuffer/vectors.test
index a67d9e2c..fa4985b1 100644
--- a/test/Feature/CBuffer/vectors.test
+++ b/test/Feature/CBuffer/vectors.test
@@ -63,6 +63,10 @@ DescriptorSets:
 # DXC's vulkan support does not layout cbuffers compatibly with DXIL
 # UNSUPPORTED: Vulkan
 
+# Clang trips on 3-element vectors in structs:
+# https://github.com/llvm/llvm-project/issues/123968
+# XFAIL: Clang
+
 # RUN: split-file %s %t
 # RUN: %dxc_target -T cs_6_5 -Fo %t.o %t/source.hlsl
 # RUN: %offloader %t/pipeline.yaml %t.o | FileCheck %s