PR c++/90490 - fix decltype issues in noexcept-specifier.

	* except.c (build_noexcept_spec): Call
	instantiate_non_dependent_expr_sfinae before
	build_converted_constant_expr instead of calling
	instantiate_non_dependent_expr after it.  Add
	processing_template_decl_sentinel.

	* g++.dg/cpp0x/noexcept43.C: New test.
	* g++.dg/cpp0x/noexcept44.C: New test.

From-SVN: r272568

gcc/cp/ChangeLog

+2019-06-21  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/90490 - fix decltype issues in noexcept-specifier.
+	* except.c (build_noexcept_spec): Call
+	instantiate_non_dependent_expr_sfinae before
+	build_converted_constant_expr instead of calling
+	instantiate_non_dependent_expr after it.  Add
+	processing_template_decl_sentinel.
+
 2019-06-21  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/90950

gcc/cp/except.c

@@ -1285,8 +1285,10 @@ build_noexcept_spec (tree expr, tsubst_flags_t complain)
   if (TREE_CODE (expr) != DEFERRED_NOEXCEPT
       && !value_dependent_expression_p (expr))
     {
+      expr = instantiate_non_dependent_expr_sfinae (expr, complain);
+      /* Don't let convert_like_real create more template codes.  */
+      processing_template_decl_sentinel s;
       expr = build_converted_constant_bool_expr (expr, complain);
-      expr = instantiate_non_dependent_expr (expr);
       expr = cxx_constant_value (expr);
     }
   if (TREE_CODE (expr) == INTEGER_CST)

gcc/testsuite/ChangeLog

+2019-06-21  Marek Polacek  <polacek@redhat.com>
+
+	PR c++/90490 - fix decltype issues in noexcept-specifier.
+	* g++.dg/cpp0x/noexcept43.C: New test.
+	* g++.dg/cpp0x/noexcept44.C: New test.
+
 2019-06-21  Matthew Beliveau  <mbelivea@redhat.com>
 
 	PR c++/90875 - added -Wswitch-outside-range option
@@ -13,7 +19,7 @@
 
 2019-06-21  Jeff Law  <law@redhat.com>
 
-        PR tree-optimization/90949
+	PR tree-optimization/90949
 	* gcc.c-torture/execute/pr90949.c: New test.
 
 2019-06-21  Marek Polacek  <polacek@redhat.com>

gcc/testsuite/g++.dg/cpp0x/noexcept43.C

+// PR c++/90490
+// { dg-do compile { target c++11 } }
+
+struct R { constexpr operator bool() { return false;} };
+
+template <typename>
+struct S {
+  void g() noexcept(decltype(R{ }) { }) {
+  }
+};

gcc/testsuite/g++.dg/cpp0x/noexcept44.C

+// PR c++/90490
+// { dg-do compile { target c++11 } }
+
+template <typename>
+struct S {
+  void g() noexcept(decltype(int{ }) { }) {
+  }
+};