On 11/03/2011 05:06 PM, Jason Merrill wrote:
I'd rather use maybe_constant_value here, but I think you don't need
to check the actual value at all; if we have decided that there is a
conversion from bool to pointer, it must be a null pointer constant,
and so false.
Ah! Thanks for the explanation, thus it seems even simpler than I
thought yesterday.
I just booted and tested the below on x86_64-linux. Ok?
Thanks again,
Paolo.
///////////////
/cp
2011-11-04 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/48420
* call.c (conversion_null_warnings): For 'false' to NULL pointer,
just check that TREE_TYPE (expr) is a BOOLEAN_TYPE.
/testsuite
2011-11-04 Paolo Carlini <paolo.carl...@oracle.com>
PR c++/48420
* g++.dg/warn/Wconversion-null-3.C: New.
Index: testsuite/g++.dg/warn/Wconversion-null-3.C
===================================================================
--- testsuite/g++.dg/warn/Wconversion-null-3.C (revision 0)
+++ testsuite/g++.dg/warn/Wconversion-null-3.C (revision 0)
@@ -0,0 +1,8 @@
+// PR c++/48420
+
+void foo(int* p);
+
+void bar() {
+ const bool kDebugMode = false;
+ foo(kDebugMode); // { dg-warning "converting 'false'" }
+}
Index: cp/call.c
===================================================================
--- cp/call.c (revision 180920)
+++ cp/call.c (working copy)
@@ -5544,7 +5544,8 @@ conversion_null_warnings (tree totype, tree expr,
}
/* Issue warnings if "false" is converted to a NULL pointer */
- else if (expr == boolean_false_node && TYPE_PTR_P (totype))
+ else if (TREE_CODE (TREE_TYPE (expr)) == BOOLEAN_TYPE
+ && TYPE_PTR_P (totype))
{
if (fn)
warning_at (input_location, OPT_Wconversion_null,
