【Linux】解决"no member named 'max_align_t'

编译遇到错误：

/usr/bin/../lib/gcc/x86_64-linux-gnu/5.4.1/../../../../include/c++/5.4.1/cstddef:51:11: error: no member named 'max_align_t' in the global namespace using ::max_align_t;

修改头文件stddef.h：

#if __STDC_VERSION__ >= 201112L || __cplusplus >= 201103L
typedef struct {
  long long __clang_max_align_nonce1
      __attribute__((__aligned__(__alignof__(long long))));
  long double __clang_max_align_nonce2
      __attribute__((__aligned__(__alignof__(long double))));
} max_align_t;
#define __CLANG_MAX_ALIGN_T_DEFINED
#endif