diff --git a/extras/Introjucer/Source/Utility/jucer_FileHelpers.h b/extras/Introjucer/Source/Utility/jucer_FileHelpers.h
index 2ec5537bda..7f97daf70f 100644
--- a/extras/Introjucer/Source/Utility/jucer_FileHelpers.h
+++ b/extras/Introjucer/Source/Utility/jucer_FileHelpers.h
@@ -33,7 +33,7 @@ namespace FileHelpers
     int64 calculateStreamHashCode (InputStream& stream);
     int64 calculateFileHashCode (const File& file);
 
-    bool overwriteFileWithNewDataIfDifferent (const File& file, const void* data, int numBytes);
+    bool overwriteFileWithNewDataIfDifferent (const File& file, const void* data, size_t numBytes);
     bool overwriteFileWithNewDataIfDifferent (const File& file, const MemoryOutputStream& newData);
     bool overwriteFileWithNewDataIfDifferent (const File& file, const String& newData);