Index: lib/Support/CommandLine.cpp
===================================================================
--- lib/Support/CommandLine.cpp
+++ lib/Support/CommandLine.cpp
@@ -439,6 +439,14 @@
 
   Value = Arg.substr(EqualPos + 1);
   Arg = Arg.substr(0, EqualPos);
+
+  // Windows Cmd Shell will not remove the '' from a --checks='abc' type command
+  // when passed via argv, unlike Linux or cygwin shells.
+  if (Triple(sys::getProcessTriple()).isOSWindows()) {
+    // Pull off the leading and trailing 's.
+    if (Value.size() > 1 && Value[0] == '\'' && Value[Value.size() - 1] == '\'')
+      Value = Value.substr(1, Value.size() - 2);
+  }
   return I->second;
 }
 
Index: unittests/Support/CommandLineTest.cpp
===================================================================
--- unittests/Support/CommandLineTest.cpp
+++ unittests/Support/CommandLineTest.cpp
@@ -914,4 +914,30 @@
   EXPECT_TRUE(MacroDefs.front().compare("HAVE_FOO") == 0);
 }
 
+TEST(CommandLineTest, WindowsCmdShellQuotesArg) {
+  if (!Triple(sys::getProcessTriple()).isOSWindows())
+    return;
+
+  StackOption<std::string, cl::opt<std::string>> Checks(
+      "checks", cl::desc("The checks"), cl::init(""));
+
+  const char *argsCmdShell[] = {"clang-tidy.exe",
+                                "-checks='-*,readability-identifier-naming'"};
+
+  EXPECT_TRUE(cl::ParseCommandLineOptions(2, argsCmdShell, StringRef(),
+                                          &llvm::nulls()));
+
+  EXPECT_TRUE(Checks.compare("-*,readability-identifier-naming") == 0);
+
+  cl::ResetAllOptionOccurrences();
+
+  const char *argsCmdShell2[] = {"clang-tidy.exe",
+                                 "-checks=-*,readability-identifier-naming"};
+
+  EXPECT_TRUE(cl::ParseCommandLineOptions(2, argsCmdShell2, StringRef(),
+                                          &llvm::nulls()));
+
+  EXPECT_TRUE(Checks.compare("-*,readability-identifier-naming") == 0);
+}
+
 } // anonymous namespace