diff --git a/clang/include/clang/Basic/DiagnosticDriverKinds.td b/clang/include/clang/Basic/DiagnosticDriverKinds.td
--- a/clang/include/clang/Basic/DiagnosticDriverKinds.td
+++ b/clang/include/clang/Basic/DiagnosticDriverKinds.td
@@ -668,6 +668,8 @@
   "invalid profile : %0">;
 def err_drv_dxc_missing_target_profile : Error<
   "target profile option (-T) is missing">;
+def err_drv_hlsl_unsupported_target : Error<
+  "HLSL code generation is unsupported for target '%0'">;
 
 def err_drv_invalid_range_dxil_validator_version : Error<
   "invalid validator version : %0\n"
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -4111,6 +4111,14 @@
   if (const Arg *A = Args.getLastArg(OPT_frandomize_layout_seed_EQ))
     Opts.RandstructSeed = A->getValue(0);
 
+  // Validate options for HLSL
+  if (Opts.HLSL) {
+    bool SupportedTarget = T.getArch() == llvm::Triple::dxil &&
+                           T.getOS() == llvm::Triple::ShaderModel;
+    if (!SupportedTarget)
+      Diags.Report(diag::err_drv_hlsl_unsupported_target) << T.str();
+  }
+
   return Diags.getNumErrors() == NumErrorsBefore;
 }
 
diff --git a/clang/test/Driver/hlsl-lang-targets.hlsl b/clang/test/Driver/hlsl-lang-targets.hlsl
new file mode 100644
--- /dev/null
+++ b/clang/test/Driver/hlsl-lang-targets.hlsl
@@ -0,0 +1,14 @@
+// RUN: not %clang -target x86_64-unknown-unknown %s 2>&1 | FileCheck %s --check-prefix=X86
+// RUN: not %clang -target dxil-unknown-unknown %s 2>&1 | FileCheck %s --check-prefix=DXIL
+// RUN: not %clang -target x86_64-unknown-shadermodel %s 2>&1 | FileCheck %s --check-prefix=SM
+// RUN: not %clang -target spirv64-unknown-unknown %s 2>&1 | FileCheck %s --check-prefix=SPIRV
+
+
+// A completely unsupported target...
+// X86: error: HLSL code generation is unsupported for target 'x86_64-unknown-unknown'
+
+// Poorly specified targets
+// DXIL: error: HLSL code generation is unsupported for target 'dxil-unknown-unknown'
+// SM: error: HLSL code generation is unsupported for target 'x86_64-unknown-shadermodel'
+
+// FIXME// SPIRV: error: HLSL code generation is unsupported for target 'spirv64-unknown-unknown'
diff --git a/clang/test/Preprocessor/predefined-macros-hlsl.c b/clang/test/Preprocessor/predefined-macros-hlsl.c
--- a/clang/test/Preprocessor/predefined-macros-hlsl.c
+++ b/clang/test/Preprocessor/predefined-macros-hlsl.c
@@ -29,20 +29,20 @@
 // PIXEL: #define __SHADER_TARGET_STAGE 0
 // VERTEX: #define __SHADER_TARGET_STAGE 1
 
-// RUN: %clang_cc1 %s -E -dM -o - -x hlsl -std=hlsl2015 | FileCheck -match-full-lines %s --check-prefixes=STD2015
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-library %s -E -dM -o - -x hlsl -std=hlsl2015 | FileCheck -match-full-lines %s --check-prefixes=STD2015
 // STD2015: #define __HLSL_VERSION 2015
 
-// RUN: %clang_cc1 %s -E -dM -o - -x hlsl -std=hlsl2016 | FileCheck -match-full-lines %s --check-prefixes=STD2016
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-library %s -E -dM -o - -x hlsl -std=hlsl2016 | FileCheck -match-full-lines %s --check-prefixes=STD2016
 // STD2016: #define __HLSL_VERSION 2016
 
-// RUN: %clang_cc1 %s -E -dM -o - -x hlsl -std=hlsl2017 | FileCheck -match-full-lines %s --check-prefixes=STD2017
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-library %s -E -dM -o - -x hlsl -std=hlsl2017 | FileCheck -match-full-lines %s --check-prefixes=STD2017
 // STD2017: #define __HLSL_VERSION 2017
 
-// RUN: %clang_cc1 %s -E -dM -o - -x hlsl -std=hlsl2018 | FileCheck -match-full-lines %s --check-prefixes=STD2018
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-library %s -E -dM -o - -x hlsl -std=hlsl2018 | FileCheck -match-full-lines %s --check-prefixes=STD2018
 // STD2018: #define __HLSL_VERSION 2018
 
-// RUN: %clang_cc1 %s -E -dM -o - -x hlsl -std=hlsl2021 | FileCheck -match-full-lines %s --check-prefixes=STD2021
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-library %s -E -dM -o - -x hlsl -std=hlsl2021 | FileCheck -match-full-lines %s --check-prefixes=STD2021
 // STD2021: #define __HLSL_VERSION 2021
 
-// RUN: %clang_cc1 %s -E -dM -o - -x hlsl -std=hlsl202x | FileCheck -match-full-lines %s --check-prefixes=STD202x
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.0-library %s -E -dM -o - -x hlsl -std=hlsl202x | FileCheck -match-full-lines %s --check-prefixes=STD202x
 // STD202x: #define __HLSL_VERSION 2029