-// <regex> in gcc is unusable in versions less than 4.9.0
-// see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=53631
-// clang defines __GNUC__ but how do the versions match?
-// disabled because of missing match_partial
-//#ifndef LYX_USE_STD_REGEX
-//# if (__GNUC__ == 4 && __GNUC_MINOR__ >= 9) || __GNUC__ > 4 || defined(USE_LLVM_LIBCPP)
-//# define LYX_USE_STD_REGEX
-//# endif
-//#endif
-