libstdc++: Remove leftover __formatter_chrono base classes.

This patch removes the __formatter_chrono<_CharT> base class from the
formatters for utc_time, gps_time, and tai_time. These formatters
are using the __formatter_duration<_CharT> member only.

libstdc++-v3/ChangeLog:

	* include/bits/chrono_io.h (formatter<chrono::utc_time, _CharT>):
	(formatter<chrono::gps_time<_Duration>, _CharT>)
	(formatter<chrono::tai_time<_Duration>, _CharT): Remove
	__formatter_chrono base class.

Reviewed-by: Jonathan Wakely <jwakely@redhat.com>
Signed-off-by: Tomasz Kamiński <tkaminsk@redhat.com>

diff --git a/libstdc++-v3/include/bits/chrono_io.h b/libstdc++-v3/include/bits/chrono_io.h
index ff7e8cfe6b9ff0b445314d7e4581241dbd09c09e..85b2013cf70408407c6dcb54bc2e54eab637e6c9 100644 (file)
--- a/libstdc++-v3/include/bits/chrono_io.h
+++ b/libstdc++-v3/include/bits/chrono_io.h
@@ -2958,7 +2958,6 @@ namespace __format
 
   template<typename _Duration, __format::__char _CharT>
     struct formatter<chrono::utc_time<_Duration>, _CharT>
-    : __format::__formatter_chrono<_CharT>
     {
       constexpr typename basic_format_parse_context<_CharT>::iterator
       parse(basic_format_parse_context<_CharT>& __pc)
@@ -3003,7 +3002,6 @@ namespace __format
 
   template<typename _Duration, __format::__char _CharT>
     struct formatter<chrono::tai_time<_Duration>, _CharT>
-    : __format::__formatter_chrono<_CharT>
     {
       constexpr typename basic_format_parse_context<_CharT>::iterator
       parse(basic_format_parse_context<_CharT>& __pc)
@@ -3039,7 +3037,6 @@ namespace __format
 
   template<typename _Duration, __format::__char _CharT>
     struct formatter<chrono::gps_time<_Duration>, _CharT>
-    : __format::__formatter_chrono<_CharT>
     {
       constexpr typename basic_format_parse_context<_CharT>::iterator
       parse(basic_format_parse_context<_CharT>& __pc)