Fixes leak of duplicate command line environment strings

runtime/bin/main.cc

Index: runtime/bin/main.cc
diff --git a/runtime/bin/main.cc b/runtime/bin/main.cc
index a90c1a45cd78f32f45495a9c3ab5c02926505817..b25f3006be59384a10622fb93b35943171670348 100644
--- a/runtime/bin/main.cc
+++ b/runtime/bin/main.cc
@@ -282,29 +282,35 @@ static bool ProcessEnvironmentOption(const char* arg,
     environment = new HashMap(&HashMap::SameStringValue, 4);
   }
   // Split the name=value part of the -Dname=value argument.
-  char* name;
-  char* value = NULL;
   const char* equals_pos = strchr(arg, '=');
   if (equals_pos == NULL) {
     // No equal sign (name without value) currently not supported.
     Log::PrintErr("No value given to -D option\n");
     return false;
-  } else {
-    int name_len = equals_pos - arg;
-    if (name_len == 0) {
-      Log::PrintErr("No name given to -D option\n");
-      return false;
-    }
-    // Split name=value into name and value.
-    name = reinterpret_cast<char*>(malloc(name_len + 1));
-    strncpy(name, arg, name_len);
-    name[name_len] = '\0';
-    value = strdup(equals_pos + 1);
   }
+
+  char* name;
+  char* value = NULL;
+  int name_len = equals_pos - arg;
+  if (name_len == 0) {
+    Log::PrintErr("No name given to -D option\n");
+    return false;
+  }
+  // Split name=value into name and value.
+  name = reinterpret_cast<char*>(malloc(name_len + 1));
+  strncpy(name, arg, name_len);
+  name[name_len] = '\0';
+  value = strdup(equals_pos + 1);
   HashMap::Entry* entry = environment->Lookup(
       GetHashmapKeyFromString(name), HashMap::StringHash(name), true);
   ASSERT(entry != NULL);  // Lookup adds an entry if key not found.
-  entry->value = value;
+  if (entry->value == NULL) {
+    entry->value = value;
+  } else {
+    free(name);
+    free(entry->value);
+    entry->value = value;
+  }

[siva, 2016/08/08 19:41:05]

how about

if (entry->value != NULL) {
  free(name);
  free(entry->value);
}
entry->value = value;

[zra, 2016/08/08 19:53:13]

Done.

   return true;
 }