Trent Mick <trentm@activestate.com>:

The common technique for printing out a pointer has been to cast to a long
and use the "%lx" printf modifier. This is incorrect on Win64 where casting
to a long truncates the pointer. The "%p" formatter should be used instead.

The problem as stated by Tim:
> Unfortunately, the C committee refused to define what %p conversion "looks
> like" -- they explicitly allowed it to be implementation-defined. Older
> versions of Microsoft C even stuck a colon in the middle of the address (in
> the days of segment+offset addressing)!

The result is that the hex value of a pointer will maybe/maybe not have a 0x
prepended to it.


Notes on the patch:

There are two main classes of changes:
- in the various repr() functions that print out pointers
- debugging printf's in the various thread_*.h files (these are why the
patch is large)


Closes SourceForge patch #100505.

1 files changed, 6 insertions, 6 deletions

diff --git a/Objects/object.c b/Objects/object.c
index 6eaff67..694aade 100644
--- a/Objects/object.c
+++ b/Objects/object.c
@@ -229,12 +229,12 @@ PyObject_Print(op, fp, flags)
 	}
 	else {
 		if (op->ob_refcnt <= 0)
-			fprintf(fp, "<refcnt %u at %lx>",
-				op->ob_refcnt, (long)op);
+			fprintf(fp, "<refcnt %u at %p>",
+				op->ob_refcnt, op);
 		else if (op->ob_type->tp_print == NULL) {
 			if (op->ob_type->tp_repr == NULL) {
-				fprintf(fp, "<%s object at %lx>",
-					op->ob_type->tp_name, (long)op);
+				fprintf(fp, "<%s object at %p>",
+					op->ob_type->tp_name, op);
 			}
 			else {
 				PyObject *s;
@@ -280,8 +280,8 @@ PyObject_Repr(v)
 		return PyString_FromString("<NULL>");
 	else if (v->ob_type->tp_repr == NULL) {
 		char buf[120];
-		sprintf(buf, "<%.80s object at %lx>",
-			v->ob_type->tp_name, (long)v);
+		sprintf(buf, "<%.80s object at %p>",
+			v->ob_type->tp_name, v);
 		return PyString_FromString(buf);
 	}
 	else {