Darwin: Misc size_t warnings

src/closures.c

@@ -264,7 +264,7 @@ static int
 open_temp_exec_file_dir (const char *dir)
 {
   static const char suffix[] = "/ffiXXXXXX";
-  int lendir = strlen (dir);
+  size_t lendir = strlen (dir);
   char *tempname = __builtin_alloca (lendir + sizeof (suffix));
 
   if (!tempname)

src/prep_cif.c

@@ -187,7 +187,7 @@ ffi_status FFI_HIDDEN ffi_prep_cif_core(ffi_cif *cif, ffi_abi abi,
 	{
 	  /* Add any padding if necessary */
 	  if (((*ptr)->alignment - 1) & bytes)
-	    bytes = ALIGN(bytes, (*ptr)->alignment);
+	    bytes = (unsigned)ALIGN(bytes, (*ptr)->alignment);
 
 #ifdef TILE
 	  if (bytes < 10 * FFI_SIZEOF_ARG &&