1 files changed, 7 insertions, 8 deletions
diff --git a/Source/cmTimestamp.cxx b/Source/cmTimestamp.cxx
index c624d0f..61b74db 100644
--- a/Source/cmTimestamp.cxx
+++ b/Source/cmTimestamp.cxx
@@ -22,7 +22,7 @@
 std::string cmTimestamp::CurrentTime(const std::string& formatString,
                                      bool utcFlag)
 {
-  time_t currentTimeT = time(0);
+  time_t currentTimeT = time(CM_NULLPTR);
   if (currentTimeT == time_t(-1)) {
     return std::string();
   }
@@ -56,14 +56,14 @@ std::string cmTimestamp::CreateTimestampFromTimeT(time_t timeT,
   struct tm timeStruct;
   memset(&timeStruct, 0, sizeof(timeStruct));
 
-  struct tm* ptr = (struct tm*)0;
+  struct tm* ptr = (struct tm*)CM_NULLPTR;
   if (utcFlag) {
     ptr = gmtime(&timeT);
   } else {
     ptr = localtime(&timeT);
   }
 
-  if (ptr == 0) {
+  if (ptr == CM_NULLPTR) {
     return std::string();
   }
 
@@ -93,10 +93,9 @@ time_t cmTimestamp::CreateUtcTimeTFromTm(struct tm& tm) const
 #else
   // From Linux timegm() manpage.
 
-  std::string tz_old = "TZ=";
-  if (const char* tz = cmSystemTools::GetEnv("TZ")) {
-    tz_old += tz;
-  }
+  std::string tz_old = "";
+  cmSystemTools::GetEnv("TZ", tz_old);
+  tz_old = "TZ=" + tz_old;
 
   // The standard says that "TZ=" or "TZ=[UNRECOGNIZED_TZ]" means UTC.
   // It seems that "TZ=" does NOT work, at least under Windows
@@ -152,7 +151,7 @@ std::string cmTimestamp::AddTimestampComponent(char flag,
         return std::string();
       }
 
-      std::stringstream ss;
+      std::ostringstream ss;
       ss << static_cast<long int>(difftime(timeT, unixEpoch));
       return ss.str();
     }