Without the triple, the test fails on a windows bot
(http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/16531/steps/stage%201%20check/logs/stdio)
because of different full type widths (unsigned long long vs unsigned long)
-// RUN: %clang_cc1 -fsyntax-only -verify -fenable-matrix %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -fsyntax-only -verify -fenable-matrix %s
typedef double double4x4 __attribute__((matrix_type(4, 4)));
typedef unsigned u4x4 __attribute__((matrix_type(4, 4)));