re PR c++/78761 (C++14, compiler generate mangled name that can not be demangled)

	PR c++/78761
	* cp-demangle.c (cplus_demangle_type): Demangle Dc as decltype(auto).
	* testsuite/demangle-expected: Add test for decltype(auto).

From-SVN: r243593

libiberty/ChangeLog

+2016-12-13  Jakub Jelinek  <jakub@redhat.com>
+
+	PR c++/78761
+	* cp-demangle.c (cplus_demangle_type): Demangle Dc as decltype(auto).
+	* testsuite/demangle-expected: Add test for decltype(auto).
+
 2016-12-12  Nathan Sidwell  <nathan@acm.org>
 
 	PR c++/78252

libiberty/cp-demangle.c

@@ -2593,7 +2593,11 @@ cplus_demangle_type (struct d_info *di)
 	  /* auto */
 	  ret = d_make_name (di, "auto", 4);
 	  break;
-	  
+	case 'c':
+	  /* decltype(auto) */
+	  ret = d_make_name (di, "decltype(auto)", 14);
+	  break;
+
 	case 'f':
 	  /* 32-bit decimal floating point */
 	  ret = d_make_builtin_type (di, &cplus_demangle_builtin_types[26]);

libiberty/testsuite/demangle-expected

@@ -4200,6 +4200,9 @@ decltype (new auto({parm#1})) f<int>(int)
 _Z1fIiERDaRKT_S1_
 auto& f<int>(int const&, int)
 --format=gnu-v3
+_Z1gIiEDcRKT_S0_
+decltype(auto) g<int>(int const&, int)
+--format=gnu-v3
 _Z1gILi1EEvR1AIXT_EER1BIXscbT_EE
 void g<1>(A<1>&, B<static_cast<bool>(1)>&)
 --format=gnu-v3