Fix #2371: Redirect Windows CRT assertions to stderr
diff --git a/googletest/src/gtest.cc b/googletest/src/gtest.cc
index a74041e..cbd48d3 100644
--- a/googletest/src/gtest.cc
+++ b/googletest/src/gtest.cc
@@ -80,6 +80,11 @@
 
 #elif GTEST_OS_WINDOWS  // We are on Windows proper.
 
+# include <windows.h>  // NOLINT
+# undef min
+
+# include <crtdbg.h>  // NOLINT
+# include <debugapi.h>  // NOLINT
 # include <io.h>  // NOLINT
 # include <sys/timeb.h>  // NOLINT
 # include <sys/types.h>  // NOLINT
@@ -91,11 +96,6 @@
 #  include <sys/time.h>  // NOLINT
 # endif  // GTEST_OS_WINDOWS_MINGW
 
-// cpplint thinks that the header is already included, so we want to
-// silence it.
-# include <windows.h>  // NOLINT
-# undef min
-
 #else
 
 // Assume other platforms have gettimeofday().
@@ -4914,6 +4914,16 @@
           0x0,                                    // Clear the following flags:
           _WRITE_ABORT_MSG | _CALL_REPORTFAULT);  // pop-up window, core dump.
 # endif
+
+    // In debug mode, the Windows CRT can crash with an assertion over invalid
+    // input (e.g. passing an invalid file descriptor).  The default handling
+    // for these assertions is to pop up a dialog and wait for user input.
+    // Instead ask the CRT to dump such assertions to stderr non-interactively.
+    if (!IsDebuggerPresent()) {
+      (void)_CrtSetReportMode(_CRT_ASSERT,
+                              _CRTDBG_MODE_FILE | _CRTDBG_MODE_DEBUG);
+      (void)_CrtSetReportFile(_CRT_ASSERT, _CRTDBG_FILE_STDERR);
+    }
   }
 #endif  // GTEST_OS_WINDOWS
 
diff --git a/googletest/test/googletest-death-test-test.cc b/googletest/test/googletest-death-test-test.cc
index 6c71fd8..814d771 100644
--- a/googletest/test/googletest-death-test-test.cc
+++ b/googletest/test/googletest-death-test-test.cc
@@ -41,7 +41,9 @@
 #if GTEST_HAS_DEATH_TEST
 
 # if GTEST_OS_WINDOWS
+#  include <fcntl.h>           // For O_BINARY
 #  include <direct.h>          // For chdir().
+#  include <io.h>
 # else
 #  include <unistd.h>
 #  include <sys/wait.h>        // For waitpid.
@@ -202,6 +204,26 @@
   return 12;
 }
 
+# if GTEST_OS_WINDOWS
+
+// Death in dbg due to Windows CRT assertion failure, not opt.
+int DieInCRTDebugElse12(int* sideeffect) {
+  if (sideeffect) *sideeffect = 12;
+
+  // Create an invalid fd by closing a valid one
+  int fdpipe[2];
+  EXPECT_EQ(_pipe(fdpipe, 256, O_BINARY), 0);
+  EXPECT_EQ(_close(fdpipe[0]), 0);
+  EXPECT_EQ(_close(fdpipe[1]), 0);
+
+  // _dup() should crash in debug mode
+  EXPECT_EQ(_dup(fdpipe[0]), -1);
+
+  return 12;
+}
+
+#endif  // GTEST_OS_WINDOWS
+
 # if GTEST_OS_WINDOWS || GTEST_OS_FUCHSIA
 
 // Tests the ExitedWithCode predicate.
@@ -632,6 +654,40 @@
 # endif
 }
 
+# if GTEST_OS_WINDOWS
+
+// Tests that EXPECT_DEBUG_DEATH works as expected when in debug mode
+// the Windows CRT crashes the process with an assertion failure.
+// 1. Asserts on death.
+// 2. Has no side effect (doesn't pop up a window or wait for user input).
+//
+// And in opt mode, it:
+// 1.  Has side effects but does not assert.
+TEST_F(TestForDeathTest, CRTDebugDeath) {
+  int sideeffect = 0;
+
+  // Put the regex in a local variable to make sure we don't get an "unused"
+  // warning in opt mode.
+  const char* regex = "dup.* : Assertion failed";
+
+  EXPECT_DEBUG_DEATH(DieInCRTDebugElse12(&sideeffect), regex)
+      << "Must accept a streamed message";
+
+# ifdef NDEBUG
+
+  // Checks that the assignment occurs in opt mode (sideeffect).
+  EXPECT_EQ(12, sideeffect);
+
+# else
+
+  // Checks that the assignment does not occur in dbg mode (no sideeffect).
+  EXPECT_EQ(0, sideeffect);
+
+# endif
+}
+
+# endif  // GTEST_OS_WINDOWS
+
 // Tests that ASSERT_DEBUG_DEATH works as expected, that is, you can stream a
 // message to it, and in debug mode it:
 // 1. Asserts on death.