... in case, we may want to do something like the below too.
Thanks,
Paolo.
///////////////////
Index: cp/cp-tree.h
===================================================================
--- cp/cp-tree.h (revision 196136)
+++ cp/cp-tree.h (working copy)
@@ -5834,6 +5834,7 @@ extern bool cast_valid_in_integral_constant_expres
extern bool cxx_type_hash_eq (const_tree, const_tree);
extern void cxx_print_statistics (void);
+extern bool maybe_warn_zero_as_null_pointer_constant (tree, location_t);
/* in ptree.c */
extern void cxx_print_xnode (FILE *, tree, int);
Index: cp/cvt.c
===================================================================
--- cp/cvt.c (revision 196136)
+++ cp/cvt.c (working copy)
@@ -203,11 +203,8 @@ cp_convert_to_pointer (tree type, tree expr, tsubs
if (null_ptr_cst_p (expr))
{
- if ((complain & tf_warning)
- && c_inhibit_evaluation_warnings == 0
- && !NULLPTR_TYPE_P (TREE_TYPE (expr)))
- warning_at (loc, OPT_Wzero_as_null_pointer_constant,
- "zero as null pointer constant");
+ if (complain & tf_warning)
+ maybe_warn_zero_as_null_pointer_constant (expr, loc);
if (TYPE_PTRMEMFUNC_P (type))
return build_ptrmemfunc (TYPE_PTRMEMFUNC_FN_TYPE (type), expr, 0,
@@ -783,7 +780,11 @@ ocp_convert (tree type, tree expr, int convtype, i
return ignore_overflows (converted, e);
}
if (NULLPTR_TYPE_P (type) && e && null_ptr_cst_p (e))
- return nullptr_node;
+ {
+ if (complain & tf_warning)
+ maybe_warn_zero_as_null_pointer_constant (e, loc);
+ return nullptr_node;
+ }
if (POINTER_TYPE_P (type) || TYPE_PTRMEM_P (type))
return fold_if_not_in_template (cp_convert_to_pointer (type, e, complain));
if (code == VECTOR_TYPE)
Index: cp/decl.c
===================================================================
--- cp/decl.c (revision 196136)
+++ cp/decl.c (working copy)
@@ -10861,15 +10861,10 @@ check_default_argument (tree decl, tree arg)
--cp_unevaluated_operand;
if (warn_zero_as_null_pointer_constant
- && c_inhibit_evaluation_warnings == 0
&& TYPE_PTR_OR_PTRMEM_P (decl_type)
&& null_ptr_cst_p (arg)
- && !NULLPTR_TYPE_P (TREE_TYPE (arg)))
- {
- warning (OPT_Wzero_as_null_pointer_constant,
- "zero as null pointer constant");
- return nullptr_node;
- }
+ && maybe_warn_zero_as_null_pointer_constant (arg, input_location))
+ return nullptr_node;
/* [dcl.fct.default]
Index: cp/tree.c
===================================================================
--- cp/tree.c (revision 196136)
+++ cp/tree.c (working copy)
@@ -3939,6 +3939,21 @@ cp_tree_operand_length (const_tree t)
return TREE_OPERAND_LENGTH (t);
}
}
+
+/* Implement -Wzero_as_null_pointer_constant. Return true if the
+ conditions for the warning hold, false otherwise. */
+bool
+maybe_warn_zero_as_null_pointer_constant (tree expr, location_t loc)
+{
+ if (c_inhibit_evaluation_warnings == 0
+ && !NULLPTR_TYPE_P (TREE_TYPE (expr)))
+ {
+ warning_at (loc, OPT_Wzero_as_null_pointer_constant,
+ "zero as null pointer constant");
+ return true;
+ }
+ return false;
+}
#if defined ENABLE_TREE_CHECKING && (GCC_VERSION >= 2007)
/* Complain that some language-specific thing hanging off a tree
Index: cp/typeck.c
===================================================================
--- cp/typeck.c (revision 196136)
+++ cp/typeck.c (working copy)
@@ -4293,13 +4293,10 @@ cp_build_binary_op (location_t location,
delta0,
integer_one_node,
complain);
-
- if ((complain & tf_warning)
- && c_inhibit_evaluation_warnings == 0
- && !NULLPTR_TYPE_P (TREE_TYPE (op1)))
- warning (OPT_Wzero_as_null_pointer_constant,
- "zero as null pointer constant");
+ if (complain & tf_warning)
+ maybe_warn_zero_as_null_pointer_constant (op1, input_location);
+
e2 = cp_build_binary_op (location,
EQ_EXPR, e2, integer_zero_node,
complain);
Index: testsuite/g++.dg/cpp0x/Wzero-as-null-pointer-constant-2.C
===================================================================
--- testsuite/g++.dg/cpp0x/Wzero-as-null-pointer-constant-2.C (revision 0)
+++ testsuite/g++.dg/cpp0x/Wzero-as-null-pointer-constant-2.C (working copy)
@@ -0,0 +1,14 @@
+// PR c++/56373
+// { dg-options "-std=c++11 -Wzero-as-null-pointer-constant" }
+
+struct shared_ptr
+{
+ shared_ptr(decltype(nullptr));
+};
+
+void f()
+{
+ shared_ptr a = 0; // { dg-warning "zero as null pointer" }
+ shared_ptr b(0); // { dg-warning "zero as null pointer" }
+ shared_ptr c{0}; // { dg-warning "zero as null pointer" }
+}
