ab56cbed60
PR libstdc++/69406 * include/bits/cpp_type_traits.h: Ensure C++ language linkage. * include/ext/type_traits.h: Likewise. * testsuite/17_intro/headers/c++2011/linkage.cc: Check autoconf macros for presence of C headers. * testsuite/ext/type_traits/add_unsigned_floating_neg.cc: Adjust dg-error line number. * testsuite/ext/type_traits/add_unsigned_integer_neg.cc: Likewise. * testsuite/ext/type_traits/remove_unsigned_floating_neg.cc: Likewise. * testsuite/ext/type_traits/remove_unsigned_integer_neg.cc: Likewise. From-SVN: r232672