Fix error exit path so that it frees the buffer before exiting the program.

runtime/bin/gen_snapshot.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 // Generate a snapshot file after loading all the scripts specified on the
 // command line.
 
 #include <stdlib.h>
 #include <string.h>
 #include <stdio.h>
 
 #include "include/dart_api.h"
 
 #include "bin/builtin.h"
 #include "bin/dartutils.h"
 #include "bin/file.h"
 #include "platform/globals.h"
 
 #define CHECK_RESULT(result)                                                   \
   if (Dart_IsError(result)) {                                                  \
+    free(snapshot_buffer);                                                     \
     fprintf(stderr, "Error: %s", Dart_GetError(result));                       \
     Dart_ExitScope();                                                          \
     Dart_ShutdownIsolate();                                                    \
     exit(255);                                                                 \
   }                                                                            \
 
 
 // Global state that indicates whether a snapshot is to be created and
 // if so which file to write the snapshot into.
 static const char* snapshot_filename = NULL;
 static bool script_snapshot = false;
 static const char* package_root = NULL;
+static uint8_t* snapshot_buffer = NULL;
 
 
 // Global state which contains a pointer to the script name for which
 // a snapshot needs to be created (NULL would result in the creation
 // of a generic snapshot that contains only the corelibs).
 static char* app_script_name = NULL;
 
 
 // Global state that captures the URL mappings specified on the command line.
 static CommandLineOptions* url_mapping = NULL;
@@ skipping 293 matching lines @@
       // this case, use the generic library tag handler.
 
       // First setup and create a generic full snapshot.
       SetupForGenericSnapshotCreation();
       uint8_t* buffer = NULL;
       intptr_t size = 0;
       result = Dart_CreateSnapshot(&buffer, &size);
       CHECK_RESULT(result);
 
       // Save the snapshot buffer as we are about to shutdown the isolate.
-      uint8_t* snapshot_buffer = reinterpret_cast<uint8_t*>(malloc(size));
+      snapshot_buffer = reinterpret_cast<uint8_t*>(malloc(size));
       ASSERT(snapshot_buffer != NULL);
       memmove(snapshot_buffer, buffer, size);
 
       // Shutdown the isolate.
       Dart_ExitScope();
       Dart_ShutdownIsolate();
 
       // Now load the specified script and create a script snapshot.
       Dart_Isolate isolate = Dart_CreateIsolate(NULL,
                                                 NULL,
                                                 snapshot_buffer,
                                                 NULL,
                                                 &error);
       if (isolate == NULL) {
         fprintf(stderr, "%s", error);
         free(error);
+        free(snapshot_buffer);
         exit(255);
       }
       Dart_EnterScope();
 
       // Setup generic library tag handler.
       result = Dart_SetLibraryTagHandler(DartUtils::LibraryTagHandler);
       CHECK_RESULT(result);
 
       // Get handle to builtin library.
       Dart_Handle builtin_lib =
@@ skipping 12 matching lines @@
       CreateAndWriteSnapshot(true);
 
       free(snapshot_buffer);
     }
   } else {
     SetupForGenericSnapshotCreation();
     CreateAndWriteSnapshot(false);
   }
   return 0;
 }