c++: ICE when late parsing noexcept/NSDMI [PR98333]

Since certain members of a class are a complete-class context
[class.mem.general]p7, we delay their parsing untile the whole class has
been parsed.  For instance, NSDMIs and noexcept-specifiers.  The order
in which we perform this delayed parsing matters; we were first parsing
NSDMIs and only they did we parse noexcept-specifiers.   That turns out
to be wrong: since NSDMIs may use noexcept-specifiers, we must process
noexcept-specifiers first.  Otherwise we'll ICE in code that doesn't
expect to see DEFERRED_PARSE.

This doesn't just shift the problem, noexcept-specifiers can use members
with a NSDMI just fine, and I've also tested a similar test with this
member function:

  bool f() { return __has_nothrow_constructor (S<true>); }

and that compiled fine too.

gcc/cp/ChangeLog:

	PR c++/98333
	* parser.c (cp_parser_class_specifier_1): Perform late-parsing
	of NSDMIs before late-parsing of noexcept-specifiers.

gcc/testsuite/ChangeLog:

	PR c++/98333
	* g++.dg/cpp0x/noexcept62.C: New test.

diff --git a/gcc/cp/parser.c b/gcc/cp/parser.c
index e67339d56f94de9c0b5b5a6f4aa34e9bf3d3b3d6..5651cfacd3c727cc68852bd122a0ac3643341e1e 100644 (file)
--- a/gcc/cp/parser.c
+++ b/gcc/cp/parser.c
@@ -25008,31 +25008,10 @@ cp_parser_class_specifier_1 (cp_parser* parser)
          maybe_end_member_template_processing ();
        }
       vec_safe_truncate (unparsed_funs_with_default_args, 0);
-      /* Now parse any NSDMIs.  */
-      save_ccp = current_class_ptr;
-      save_ccr = current_class_ref;
-      FOR_EACH_VEC_SAFE_ELT (unparsed_nsdmis, ix, decl)
-       {
-         if (class_type != DECL_CONTEXT (decl))
-           {
-             if (pushed_scope)
-               pop_scope (pushed_scope);
-             class_type = DECL_CONTEXT (decl);
-             pushed_scope = push_scope (class_type);
-           }
-         inject_this_parameter (class_type, TYPE_UNQUALIFIED);
-         cp_parser_late_parsing_nsdmi (parser, decl);
-       }
-      vec_safe_truncate (unparsed_nsdmis, 0);
-      current_class_ptr = save_ccp;
-      current_class_ref = save_ccr;
-      if (pushed_scope)
-       pop_scope (pushed_scope);
 
       /* If there are noexcept-specifiers that have not yet been processed,
-        take care of them now.  */
-      class_type = NULL_TREE;
-      pushed_scope = NULL_TREE;
+        take care of them now.  Do this before processing NSDMIs as they
+        may depend on noexcept-specifiers already having been processed.  */
       FOR_EACH_VEC_SAFE_ELT (unparsed_noexcepts, ix, decl)
        {
          tree ctx = DECL_CONTEXT (decl);
@@ -25084,6 +25063,25 @@ cp_parser_class_specifier_1 (cp_parser* parser)
          maybe_end_member_template_processing ();
        }
       vec_safe_truncate (unparsed_noexcepts, 0);
+
+      /* Now parse any NSDMIs.  */
+      save_ccp = current_class_ptr;
+      save_ccr = current_class_ref;
+      FOR_EACH_VEC_SAFE_ELT (unparsed_nsdmis, ix, decl)
+       {
+         if (class_type != DECL_CONTEXT (decl))
+           {
+             if (pushed_scope)
+               pop_scope (pushed_scope);
+             class_type = DECL_CONTEXT (decl);
+             pushed_scope = push_scope (class_type);
+           }
+         inject_this_parameter (class_type, TYPE_UNQUALIFIED);
+         cp_parser_late_parsing_nsdmi (parser, decl);
+       }
+      vec_safe_truncate (unparsed_nsdmis, 0);
+      current_class_ptr = save_ccp;
+      current_class_ref = save_ccr;
       if (pushed_scope)
        pop_scope (pushed_scope);
 

diff --git a/gcc/testsuite/g++.dg/cpp0x/noexcept62.C b/gcc/testsuite/g++.dg/cpp0x/noexcept62.C
new file mode 100644 (file)
index 0000000..53606c7
--- /dev/null
+++ b/gcc/testsuite/g++.dg/cpp0x/noexcept62.C
@@ -0,0 +1,10 @@
+// PR c++/98333
+// { dg-do compile { target c++11 } }
+
+struct T {
+  template <bool N>
+  struct S {
+    S () noexcept (N) {}
+  };
+  int a = __has_nothrow_constructor (S<true>);
+};