libstdc++: Include C++17 features in doxygen API docs

libstdc++-v3/ChangeLog:

	* doc/doxygen/user.cfg.in (PREDEFINED): Use __cplusplus=201703L
	so that C++17 features are documented.

diff --git a/libstdc++-v3/doc/doxygen/user.cfg.in b/libstdc++-v3/doc/doxygen/user.cfg.in
index 19f8ffd823082a92a7bf57b47e36c2ba36e35670..4495b1c9edefe8bc460b78c3df351cc860ee0304 100644 (file)
--- a/libstdc++-v3/doc/doxygen/user.cfg.in
+++ b/libstdc++-v3/doc/doxygen/user.cfg.in
@@ -2250,7 +2250,7 @@ INCLUDE_FILE_PATTERNS  =
 # recursively expanded use the := operator instead of the = operator.
 # This tag requires that the tag ENABLE_PREPROCESSING is set to YES.
 
-PREDEFINED             = __cplusplus=201402L \
+PREDEFINED             = __cplusplus=201703L \
                          __GTHREADS \
                          _GLIBCXX_HAS_GTHREADS \
                          _GLIBCXX_HAVE_TLS \