[Python-Dev] nested classes leaking in compiler

Fri Mar 28 18:46:29 CET 2008

On Fri, Mar 28, 2008 at 11:50 AM, Georg Brandl <g.brandl at gmx.net> wrote:
> While preparing the Python-AST compilation patch, I noticed that each
> class nested in a class leaks one reference (2.5 and trunk).
>> It wasn't found by regrtest -R because it only happens on compiling,
> and it seems that all snippets compiled during the tests as opposed to
> on import didn't contain such a construct.
>> The AST generation stage is fine, the leak happens somehwere
> after that (I suspect the symtable code). It would be nice if someone
> who understands more about that code than I do could fix this.

The problem is actually in compile.c, in compiler_class():
Each compilation scope holds the name of the enclosing class (for
__name mangling).
In the case of nested classes, the inner scope is first initialized
with the outer class name, then replaced with the inner class name.
But a Py_XDECREF(c->u->u_private) is missing here...
I will submit the correction in a few hours.
-- 
Amaury Forgeot d'Arc