diff --git a/src/include/utility.cpp b/src/include/utility.cpp
index 01d1b7119..15e937063 100755
--- a/src/include/utility.cpp
+++ b/src/include/utility.cpp
@@ -122,13 +122,13 @@ bool fcopy(
 			  return error_box(FR("Impossibile scrivere il file '%s'\nper copiare il file '%s'\nErrore %d"), dest, orig, errno);
 		}
 
-		const int size = 16*1024;
+		const size_t size = 16*1024;
 		TString buffer(size);
 	
 		bool ok = true;
 		while (ok)
 		{
-			const word letti = fread(buffer.get_buffer(), 1, size, i);
+			const size_t letti = fread(buffer.get_buffer(), 1, size, i);
 			ok = fwrite(buffer.get_buffer(), 1, letti, o) == letti;
 			if (letti < size) break;
 		}
diff --git a/src/include/utility.h b/src/include/utility.h
index 5eb7900ec..3320559ec 100755
--- a/src/include/utility.h
+++ b/src/include/utility.h
@@ -16,8 +16,8 @@
 #include <lffiles.h>
 
 #define STRINGIFY(x) #x
+#define SAFE_DELETE(p) { if( (p) != nullptr ) delete (p); (p) = nullptr; }
 #define TOSTRING(x) STRINGIFY(x)
-#define SAFE_DELETE(p) { delete p; p = NULL; }
 #define DEBUG_ENABLED is_debug_station()
 
 bool    sirio_codesigning(const TFilename& filename, bool verify = false);