diff --git a/googletest/src/gtest-filepath.cc b/googletest/src/gtest-filepath.cc
index a7e65c0..9504f0f 100644
--- a/googletest/src/gtest-filepath.cc
+++ b/googletest/src/gtest-filepath.cc
@@ -38,9 +38,6 @@
 #elif GTEST_OS_WINDOWS
 # include <direct.h>
 # include <io.h>
-#elif GTEST_OS_SYMBIAN
-// Symbian OpenC has PATH_MAX in sys/syslimits.h
-# include <sys/syslimits.h>
 #else
 # include <limits.h>
 # include <climits>  // Some Linux distributions define PATH_MAX here.
@@ -95,13 +92,15 @@
 
 // Returns the current working directory, or "" if unsuccessful.
 FilePath FilePath::GetCurrentDir() {
-#if GTEST_OS_WINDOWS_MOBILE || GTEST_OS_WINDOWS_PHONE || GTEST_OS_WINDOWS_RT
-  // Windows CE doesn't have a current directory, so we just return
+#if GTEST_OS_WINDOWS_MOBILE || GTEST_OS_WINDOWS_PHONE ||         \
+    GTEST_OS_WINDOWS_RT || GTEST_OS_ESP8266 || GTEST_OS_ESP32 || \
+    GTEST_OS_XTENSA
+  // These platforms do not have a current directory, so we just return
   // something reasonable.
   return FilePath(kCurrentDirectoryString);
 #elif GTEST_OS_WINDOWS
   char cwd[GTEST_PATH_MAX_ + 1] = { '\0' };
-  return FilePath(_getcwd(cwd, sizeof(cwd)) == NULL ? "" : cwd);
+  return FilePath(_getcwd(cwd, sizeof(cwd)) == nullptr ? "" : cwd);
 #else
   char cwd[GTEST_PATH_MAX_ + 1] = { '\0' };
   char* result = getcwd(cwd, sizeof(cwd));
@@ -109,9 +108,9 @@
   // getcwd will likely fail in NaCl due to the sandbox, so return something
   // reasonable. The user may have provided a shim implementation for getcwd,
   // however, so fallback only when failure is detected.
-  return FilePath(result == NULL ? kCurrentDirectoryString : cwd);
+  return FilePath(result == nullptr ? kCurrentDirectoryString : cwd);
 # endif  // GTEST_OS_NACL
-  return FilePath(result == NULL ? "" : cwd);
+  return FilePath(result == nullptr ? "" : cwd);
 #endif  // GTEST_OS_WINDOWS_MOBILE
 }
 
@@ -136,8 +135,8 @@
 #if GTEST_HAS_ALT_PATH_SEP_
   const char* const last_alt_sep = strrchr(c_str(), kAlternatePathSeparator);
   // Comparing two pointers of which only one is NULL is undefined.
-  if (last_alt_sep != NULL &&
-      (last_sep == NULL || last_alt_sep > last_sep)) {
+  if (last_alt_sep != nullptr &&
+      (last_sep == nullptr || last_alt_sep > last_sep)) {
     return last_alt_sep;
   }
 #endif
@@ -165,7 +164,7 @@
   const char* const last_sep = FindLastPathSeparator();
   std::string dir;
   if (last_sep) {
-    dir = std::string(c_str(), last_sep + 1 - c_str());
+    dir = std::string(c_str(), static_cast<size_t>(last_sep + 1 - c_str()));
   } else {
     dir = kCurrentDirectoryString;
   }
@@ -250,9 +249,6 @@
 // root directory per disk drive.)
 bool FilePath::IsRootDirectory() const {
 #if GTEST_OS_WINDOWS
-  // FIXME: on Windows a network share like
-  // \\server\share can be a root directory, although it cannot be the
-  // current directory.  Handle this properly.
   return pathname_.length() == 3 && IsAbsolutePath();
 #else
   return pathname_.length() == 1 && IsPathSeparator(pathname_.c_str()[0]);
@@ -324,10 +320,13 @@
 #if GTEST_OS_WINDOWS_MOBILE
   FilePath removed_sep(this->RemoveTrailingPathSeparator());
   LPCWSTR unicode = String::AnsiToUtf16(removed_sep.c_str());
-  int result = CreateDirectory(unicode, NULL) ? 0 : -1;
+  int result = CreateDirectory(unicode, nullptr) ? 0 : -1;
   delete [] unicode;
 #elif GTEST_OS_WINDOWS
   int result = _mkdir(pathname_.c_str());
+#elif GTEST_OS_ESP8266 || GTEST_OS_XTENSA
+  // do nothing
+  int result = 0;
 #else
   int result = mkdir(pathname_.c_str(), 0777);
 #endif  // GTEST_OS_WINDOWS_MOBILE
@@ -350,35 +349,20 @@
 // Removes any redundant separators that might be in the pathname.
 // For example, "bar///foo" becomes "bar/foo". Does not eliminate other
 // redundancies that might be in a pathname involving "." or "..".
-// FIXME: handle Windows network shares (e.g. \\server\share).
 void FilePath::Normalize() {
-  if (pathname_.c_str() == NULL) {
-    pathname_ = "";
-    return;
-  }
-  const char* src = pathname_.c_str();
-  char* const dest = new char[pathname_.length() + 1];
-  char* dest_ptr = dest;
-  memset(dest_ptr, 0, pathname_.length() + 1);
+  auto out = pathname_.begin();
 
-  while (*src != '\0') {
-    *dest_ptr = *src;
-    if (!IsPathSeparator(*src)) {
-      src++;
+  for (const char character : pathname_) {
+    if (!IsPathSeparator(character)) {
+      *(out++) = character;
+    } else if (out == pathname_.begin() || *std::prev(out) != kPathSeparator) {
+      *(out++) = kPathSeparator;
     } else {
-#if GTEST_HAS_ALT_PATH_SEP_
-      if (*dest_ptr == kAlternatePathSeparator) {
-        *dest_ptr = kPathSeparator;
-      }
-#endif
-      while (IsPathSeparator(*src))
-        src++;
+      continue;
     }
-    dest_ptr++;
   }
-  *dest_ptr = '\0';
-  pathname_ = dest;
-  delete[] dest;
+
+  pathname_.erase(out, pathname_.end());
 }
 
 }  // namespace internal