Hi,
curiously, convert_nontype_argument still has most of its error calls
not protected by complain & tf_error. The obvious fix works for this
SFINAE issue. Not a regression, but could be safe for the branch too?
Tested x86_64-linux.
Thanks,
Paolo.
//////////////////////
/cp
2014-05-07 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/61083
* pt.c (convert_nontype_argument): Protect all the error calls
with complain & tf_error.
/testsuite
2014-05-07 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/61083
* g++.dg/cpp0x/sfinae50.C: New.
Index: cp/pt.c
===================================================================
--- cp/pt.c (revision 210180)
+++ cp/pt.c (working copy)
@@ -5812,17 +5812,18 @@ convert_nontype_argument (tree type, tree expr, ts
{
if (VAR_P (expr))
{
- error ("%qD is not a valid template argument "
- "because %qD is a variable, not the address of "
- "a variable",
- expr, expr);
+ if (complain & tf_error)
+ error ("%qD is not a valid template argument "
+ "because %qD is a variable, not the address of "
+ "a variable", expr, expr);
return NULL_TREE;
}
if (POINTER_TYPE_P (expr_type))
{
- error ("%qE is not a valid template argument for %qT "
- "because it is not the address of a variable",
- expr, type);
+ if (complain & tf_error)
+ error ("%qE is not a valid template argument for %qT "
+ "because it is not the address of a variable",
+ expr, type);
return NULL_TREE;
}
/* Other values, like integer constants, might be valid
@@ -5837,23 +5838,24 @@ convert_nontype_argument (tree type, tree expr, ts
? TREE_OPERAND (expr, 0) : expr);
if (!VAR_P (decl))
{
- error ("%qE is not a valid template argument of type %qT "
- "because %qE is not a variable",
- expr, type, decl);
+ if (complain & tf_error)
+ error ("%qE is not a valid template argument of type %qT "
+ "because %qE is not a variable", expr, type, decl);
return NULL_TREE;
}
else if (cxx_dialect < cxx11 && !DECL_EXTERNAL_LINKAGE_P (decl))
{
- error ("%qE is not a valid template argument of type %qT "
- "because %qD does not have external linkage",
- expr, type, decl);
+ if (complain & tf_error)
+ error ("%qE is not a valid template argument of type %qT "
+ "because %qD does not have external linkage",
+ expr, type, decl);
return NULL_TREE;
}
else if (cxx_dialect >= cxx11 && decl_linkage (decl) == lk_none)
{
- error ("%qE is not a valid template argument of type %qT "
- "because %qD has no linkage",
- expr, type, decl);
+ if (complain & tf_error)
+ error ("%qE is not a valid template argument of type %qT "
+ "because %qD has no linkage", expr, type, decl);
return NULL_TREE;
}
}
@@ -5881,15 +5883,17 @@ convert_nontype_argument (tree type, tree expr, ts
if (!at_least_as_qualified_p (TREE_TYPE (type), expr_type))
{
- error ("%qE is not a valid template argument for type %qT "
- "because of conflicts in cv-qualification", expr, type);
+ if (complain & tf_error)
+ error ("%qE is not a valid template argument for type %qT "
+ "because of conflicts in cv-qualification", expr, type);
return NULL_TREE;
}
if (!real_lvalue_p (expr))
{
- error ("%qE is not a valid template argument for type %qT "
- "because it is not an lvalue", expr, type);
+ if (complain & tf_error)
+ error ("%qE is not a valid template argument for type %qT "
+ "because it is not an lvalue", expr, type);
return NULL_TREE;
}
@@ -5905,9 +5909,10 @@ convert_nontype_argument (tree type, tree expr, ts
expr = TREE_OPERAND (expr, 0);
if (DECL_P (expr))
{
- error ("%q#D is not a valid template argument for type %qT "
- "because a reference variable does not have a constant "
- "address", expr, type);
+ if (complain & tf_error)
+ error ("%q#D is not a valid template argument for type %qT "
+ "because a reference variable does not have a constant "
+ "address", expr, type);
return NULL_TREE;
}
}
@@ -5914,17 +5919,19 @@ convert_nontype_argument (tree type, tree expr, ts
if (!DECL_P (expr))
{
- error ("%qE is not a valid template argument for type %qT "
- "because it is not an object with external linkage",
- expr, type);
+ if (complain & tf_error)
+ error ("%qE is not a valid template argument for type %qT "
+ "because it is not an object with external linkage",
+ expr, type);
return NULL_TREE;
}
if (!DECL_EXTERNAL_LINKAGE_P (expr))
{
- error ("%qE is not a valid template argument for type %qT "
- "because object %qD has not external linkage",
- expr, type, expr);
+ if (complain & tf_error)
+ error ("%qE is not a valid template argument for type %qT "
+ "because object %qD has not external linkage",
+ expr, type, expr);
return NULL_TREE;
}
@@ -5966,9 +5973,13 @@ convert_nontype_argument (tree type, tree expr, ts
{
if (TREE_CODE (expr) == ADDR_EXPR)
{
- error ("%qE is not a valid template argument for type %qT "
- "because it is a pointer", expr, type);
- inform (input_location, "try using %qE instead", TREE_OPERAND (expr,
0));
+ if (complain & tf_error)
+ {
+ error ("%qE is not a valid template argument for type %qT "
+ "because it is a pointer", expr, type);
+ inform (input_location, "try using %qE instead",
+ TREE_OPERAND (expr, 0));
+ }
return NULL_TREE;
}
@@ -6006,13 +6017,16 @@ convert_nontype_argument (tree type, tree expr, ts
provide a superior diagnostic. */
if (!same_type_p (TREE_TYPE (expr), type))
{
- error ("%qE is not a valid template argument for type %qT "
- "because it is of type %qT", expr, type,
- TREE_TYPE (expr));
- /* If we are just one standard conversion off, explain. */
- if (can_convert_standard (type, TREE_TYPE (expr), complain))
- inform (input_location,
- "standard conversions are not allowed in this context");
+ if (complain & tf_error)
+ {
+ error ("%qE is not a valid template argument for type %qT "
+ "because it is of type %qT", expr, type,
+ TREE_TYPE (expr));
+ /* If we are just one standard conversion off, explain. */
+ if (can_convert_standard (type, TREE_TYPE (expr), complain))
+ inform (input_location,
+ "standard conversions are not allowed in this context");
+ }
return NULL_TREE;
}
}
@@ -6035,8 +6049,9 @@ convert_nontype_argument (tree type, tree expr, ts
{
if (expr != nullptr_node)
{
- error ("%qE is not a valid template argument for type %qT "
- "because it is of type %qT", expr, type, TREE_TYPE (expr));
+ if (complain & tf_error)
+ error ("%qE is not a valid template argument for type %qT "
+ "because it is of type %qT", expr, type, TREE_TYPE (expr));
return NULL_TREE;
}
return expr;
Index: testsuite/g++.dg/cpp0x/sfinae50.C
===================================================================
--- testsuite/g++.dg/cpp0x/sfinae50.C (revision 0)
+++ testsuite/g++.dg/cpp0x/sfinae50.C (working copy)
@@ -0,0 +1,41 @@
+// PR c++/61083
+// { dg-do compile { target c++11 } }
+
+template<typename T> T declval();
+
+template<typename T, typename U>
+struct is_same {
+ static const bool value = false;
+};
+
+template<typename T>
+struct is_same<T, T> {
+ static const bool value = true;
+};
+
+struct true_type {};
+struct false_type {};
+
+template <typename T>
+struct is_foo {
+private:
+ template<typename U, U> struct helper {};
+
+ template <typename Z> static auto
+ test(Z z) -> decltype(helper<void (Z::*)() const, &Z::foo>(), true_type());
+
+ template <typename> static auto test(...) -> false_type;
+
+public:
+ enum { value = is_same<decltype(test<T>(declval<T>())), true_type>::value };
+};
+
+struct A {
+ int foo();
+ void foo() const;
+};
+
+struct A1 : public A {};
+
+static_assert (is_foo<A>::value == 1, "");
+static_assert (is_foo<A1>::value == 0, "");
