Hi,
I think submitter is right that with -Wzero-as-null-pointer-constant we
want to warn also for zero converted to nullptr_t, not just pointer
types. In that case the below is the simplest fix I could figure out,
passes testing on x86_64-linux. Otherwise I guess we should simply close
the PR.
Thanks,
Paolo.
//////////////////////
/cp
2013-02-18 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/56373
* cvt.c (ocp_convert): Emit -Wzero-as-null-pointer-constant
diagnostics for zero converted to nullptr_t.
/testsuite
2013-02-18 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/56373
* g++.dg/cpp0x/Wzero-as-null-pointer-constant-2.C: New.
Index: cp/cvt.c
===================================================================
--- cp/cvt.c (revision 196099)
+++ cp/cvt.c (working copy)
@@ -783,7 +783,14 @@ 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)
+ && c_inhibit_evaluation_warnings == 0
+ && !NULLPTR_TYPE_P (TREE_TYPE (e)))
+ warning_at (loc, OPT_Wzero_as_null_pointer_constant,
+ "zero as null pointer constant");
+ 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: 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" }
+}
