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
@@ -273,6 +273,8 @@
     : Error<"%0 is not supported with -fembed-bitcode">;
 def err_drv_bitcode_unsupported_on_toolchain : Error<
   "-fembed-bitcode is not supported on versions of iOS prior to 6.0">;
+def err_drv_stack_clash_protection_unsupported_on_toolchain : Error<
+  "-fstack-clash-protection is not supported on %0">;
 
 def err_drv_invalid_malign_branch_EQ : Error<
   "invalid argument '%0' to -malign-branch=; each element must be one of: %1">;
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -3077,12 +3077,15 @@
   }
 }
 
-static void RenderSCPOptions(const ToolChain &TC, const ArgList &Args,
-                             ArgStringList &CmdArgs) {
+static void RenderSCPOptions(const Driver &D, const ToolChain &TC,
+                             const ArgList &Args, ArgStringList &CmdArgs) {
   const llvm::Triple &EffectiveTriple = TC.getEffectiveTriple();
 
-  if (!EffectiveTriple.isOSLinux())
+  if (EffectiveTriple.isOSWindows() || EffectiveTriple.isOSDarwin()) {
+    D.Diag(diag::err_drv_stack_clash_protection_unsupported_on_toolchain)
+	<< EffectiveTriple.getOSName();
     return;
+  }
 
   if (!EffectiveTriple.isX86() && !EffectiveTriple.isSystemZ() &&
       !EffectiveTriple.isPPC64())
@@ -4045,7 +4048,7 @@
 
   // A header module compilation doesn't have a main input file, so invent a
   // fake one as a placeholder.
-  const char *ModuleName = [&]{
+  const char *ModuleName = [&] {
     auto *ModuleNameArg = Args.getLastArg(options::OPT_fmodule_name_EQ);
     return ModuleNameArg ? ModuleNameArg->getValue() : "";
   }();
@@ -5551,7 +5554,7 @@
     CmdArgs.push_back(Args.MakeArgString("-mspeculative-load-hardening"));
 
   RenderSSPOptions(D, TC, Args, CmdArgs, KernelOrKext);
-  RenderSCPOptions(TC, Args, CmdArgs);
+  RenderSCPOptions(D, TC, Args, CmdArgs);
   RenderTrivialAutoVarInitOptions(D, TC, Args, CmdArgs);
 
   // Translate -mstackrealign