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
@@ -6598,7 +6598,6 @@
     CmdArgs.push_back(
         Args.MakeArgString("-fms-compatibility-version=" + MSVT.getAsString()));
 
-  bool IsMSVC2015Compatible = MSVT.getMajor() >= 19;
   if (ImplyVCPPCVer) {
     StringRef LanguageStandard;
     if (const Arg *StdArg = Args.getLastArg(options::OPT__SLASH_std)) {
@@ -6628,12 +6627,8 @@
             << StdArg->getAsString(Args);
     }
 
-    if (LanguageStandard.empty()) {
-      if (IsMSVC2015Compatible)
-        LanguageStandard = "-std=c++14";
-      else
-        LanguageStandard = "-std=c++11";
-    }
+    if (LanguageStandard.empty())
+      LanguageStandard = "-std=c++14";
 
     CmdArgs.push_back(LanguageStandard.data());
   }
@@ -6648,12 +6643,10 @@
   else if (Args.hasArg(options::OPT_fno_declspec))
     CmdArgs.push_back("-fno-declspec"); // Explicitly disabling __declspec.
 
-  // -fthreadsafe-static is default, except for MSVC compatibility versions less
-  // than 19.
+  // -fthreadsafe-static is default, except for OpenCL.
   if (!Args.hasFlag(options::OPT_fthreadsafe_statics,
                     options::OPT_fno_threadsafe_statics,
-                    !types::isOpenCL(InputType) &&
-                        (!IsWindowsMSVC || IsMSVC2015Compatible)))
+                    !types::isOpenCL(InputType)))
     CmdArgs.push_back("-fno-threadsafe-statics");
 
   // -fno-delayed-template-parsing is default, except when targeting MSVC.
diff --git a/clang/test/Driver/cl-options.c b/clang/test/Driver/cl-options.c
--- a/clang/test/Driver/cl-options.c
+++ b/clang/test/Driver/cl-options.c
@@ -578,9 +578,6 @@
 // Z7_gdwarf: "-debug-info-kind=constructor"
 // Z7_gdwarf: "-dwarf-version=
 
-// RUN: %clang_cl -fmsc-version=1800 -TP -### -- %s 2>&1 | FileCheck -check-prefix=CXX11 %s
-// CXX11: -std=c++11
-
 // RUN: %clang_cl -fmsc-version=1900 -TP -### -- %s 2>&1 | FileCheck -check-prefix=CXX14 %s
 // CXX14: -std=c++14
 
diff --git a/clang/test/Driver/cl-zc.cpp b/clang/test/Driver/cl-zc.cpp
--- a/clang/test/Driver/cl-zc.cpp
+++ b/clang/test/Driver/cl-zc.cpp
@@ -91,11 +91,6 @@
 // RUN: %clang_cl /c -### /Zc:ternary- -- %s 2>&1 | FileCheck -check-prefix=TERNARY-OFF %s
 // TERNARY-OFF: argument unused during compilation
 
-// thread safe statics are off for versions < 19.
-// RUN: %clang_cl /c -### -fms-compatibility-version=18 -- %s 2>&1 | FileCheck -check-prefix=NoThreadSafeStatics %s
-// RUN: %clang_cl /Zc:threadSafeInit /Zc:threadSafeInit- /c -### -- %s 2>&1 | FileCheck -check-prefix=NoThreadSafeStatics %s
-// NoThreadSafeStatics: "-fno-threadsafe-statics"
-
 // RUN: %clang_cl /Zc:threadSafeInit /c -### -- %s 2>&1 | FileCheck -check-prefix=ThreadSafeStatics %s
 // ThreadSafeStatics-NOT: "-fno-threadsafe-statics"