Re: [C++ Patch] PR 58882

2014-12-15 Thread Jason Merrill

OK.

Jason


[C++ Patch] PR 58882

2014-12-14 Thread Paolo Carlini

Hi,

in order to handle correctly the testcase, thus do not ICE on it, I 
think we have simply to replace the existing gcc_unreachable with a 
normal error call. Additionally, I noticed that we aren't handling 
correctly things like constexpr user-defined type-conversion operators, 
thus I added the kind of build_expr_type_conversion / 
maybe_constant_value massaging which we are already using elsewhere. 
Finally, we have got an accepts-invalid issue with scoped enumerations, 
thus the INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P check.


Tested x86_64-linux.

Thanks,
Paolo.


/cp
2014-12-14  Paolo Carlini  paolo.carl...@oracle.com

PR c++/58882
* decl.c (check_array_designated_initializer): Diagnose gracefully
C99 designators which aren't integral constant-expressions; allow
constexpr user-defined type conversion operators.

/testsuite
2014-12-14  Paolo Carlini  paolo.carl...@oracle.com

PR c++/58882
* g++.dg/ext/desig8.C: New.
* g++.dg/cpp0x/desig1.C: Likewise.
Index: cp/decl.c
===
--- cp/decl.c   (revision 218716)
+++ cp/decl.c   (working copy)
@@ -4996,18 +4996,22 @@ check_array_designated_initializer (constructor_el
  return false;
}
 
-  ce-index = cxx_constant_value (ce-index);
-
-  if (TREE_CODE (ce-index) == INTEGER_CST)
+  tree ce_index = build_expr_type_conversion (WANT_INT | WANT_ENUM,
+ ce-index, true);
+  if (ce_index
+  INTEGRAL_OR_UNSCOPED_ENUMERATION_TYPE_P (TREE_TYPE (ce_index))
+  (TREE_CODE (ce_index = maybe_constant_value (ce_index))
+ == INTEGER_CST))
{
  /* A C99 designator is OK if it matches the current index.  */
- if (wi::eq_p (ce-index, index))
+ if (wi::eq_p (ce_index, index))
return true;
  else
sorry (non-trivial designated initializers not supported);
}
   else
-   gcc_unreachable ();
+   error (C99 designator %qE is not an integral constant-expression,
+  ce-index);
 
   return false;
 }
Index: testsuite/g++.dg/cpp0x/desig1.C
===
--- testsuite/g++.dg/cpp0x/desig1.C (revision 0)
+++ testsuite/g++.dg/cpp0x/desig1.C (working copy)
@@ -0,0 +1,27 @@
+// PR c++/58882
+// { dg-do compile { target c++11 } }
+
+struct A
+{
+  constexpr operator int() const { return 0; }
+};
+
+int a[] = { [A()] = 0 };
+
+enum E { e0 };
+
+struct B
+{
+  constexpr operator E() const { return E::e0; }
+};
+
+int b[] = { [B()] = 0 };
+
+enum class SE { se0 };
+
+struct C
+{
+  constexpr operator SE() const { return SE::se0; }
+};
+
+int c[] = { [C()] = 0 }; // { dg-error integral constant-expression }
Index: testsuite/g++.dg/ext/desig8.C
===
--- testsuite/g++.dg/ext/desig8.C   (revision 0)
+++ testsuite/g++.dg/ext/desig8.C   (working copy)
@@ -0,0 +1,3 @@
+// PR c++/58882
+
+int a[] = { [0.] = 0 }; // { dg-error integral constant-expression }