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, 9 insertions, 9 deletions

diff --git a/Objects/classobject.c b/Objects/classobject.c
index 4653d27..17b7bf4 100644
--- a/Objects/classobject.c
+++ b/Objects/classobject.c
@@ -353,11 +353,11 @@ class_repr(op)
 	else
 		name = PyString_AsString(op->cl_name);
 	if (mod == NULL || !PyString_Check(mod))
-		sprintf(buf, "<class ?.%.100s at %lx>", name, (long)op);
+		sprintf(buf, "<class ?.%.100s at %p>", name, op);
 	else
-		sprintf(buf, "<class %.50s.%.50s at %lx>",
+		sprintf(buf, "<class %.50s.%.50s at %p>",
 			PyString_AsString(mod),
-			name, (long)op);
+			name, op);
 	return PyString_FromString(buf);
 }
 
@@ -805,12 +805,12 @@ instance_repr(inst)
 			cname = "?";
 		PyErr_Clear();
 		if (mod == NULL || !PyString_Check(mod))
-			sprintf(buf, "<?.%.100s instance at %lx>",
-				cname, (long)inst);
+			sprintf(buf, "<?.%.100s instance at %p>",
+				cname, inst);
 		else
-			sprintf(buf, "<%.50s.%.50s instance at %lx>",
+			sprintf(buf, "<%.50s.%.50s instance at %p>",
 				PyString_AsString(mod),
-				cname, (long)inst);
+				cname, inst);
 		return PyString_FromString(buf);
 	}
 	res = PyEval_CallObject(func, (PyObject *)NULL);
@@ -1704,8 +1704,8 @@ instancemethod_repr(a)
 			icname = PyString_AsString(iclassname);
 		else
 			icname = "?";
-		sprintf(buf, "<method %.60s.%.60s of %.60s instance at %lx>",
-			fcname, fname, icname, (long)self);
+		sprintf(buf, "<method %.60s.%.60s of %.60s instance at %p>",
+			fcname, fname, icname, self);
 	}
 	Py_XDECREF(funcname);
 	return PyString_FromString(buf);