- && ((! defined _DONT_USE_CTYPE_INLINE_ \
- && (defined __GNUC__ || defined __cplusplus)) \
- || (defined _FORTIFY_SOURCE && 0 < _FORTIFY_SOURCE \
- && defined __GNUC__ && ! defined __cplusplus)))
+ && (defined __header_inline \
+ ? (defined __cplusplus && defined __GNUC_STDC_INLINE__ \
+ && ! defined __clang__) \
+ : ((! defined _DONT_USE_CTYPE_INLINE_ \
+ && (defined __GNUC__ || defined __cplusplus)) \
+ || (defined _FORTIFY_SOURCE && 0 < _FORTIFY_SOURCE \
+ && defined __GNUC__ && ! defined __cplusplus))))