+2019-07-02 Jonathan Wakely <jwakely@redhat.com>
+
+ * include/bits/c++config (_GLIBCXX_HAVE_BUILTIN_LAUNDER)
+ (_GLIBCXX_HAVE_BUILTIN_IS_CONSTANT_EVALUATED): Use __has_builtin
+ instead of __is_identifier to detect Clang support.
+
2019-07-02 Jim Wilson <jimw@sifive.com>
* configure.ac (BUILD_PDF): Also test for doxygen, dot, xsltproc,