[Cython] Compiler crash fix

[mark florisson]

On 22 May 2013 10:13, Nikita Nemkin <nikita at nemkin.ru> wrote:
> Hi,
>
> Someone please apply this patch (too simple for pull request):
>
> diff --git a/Cython/Compiler/ExprNodes.py b/Cython/Compiler/ExprNodes.py
> index 0406fad..640d002 100755
> --- a/Cython/Compiler/ExprNodes.py
> +++ b/Cython/Compiler/ExprNodes.py
> @@ -4993,7 +4993,7 @@ class AttributeNode(ExprNode):
>            # creates a corresponding NameNode and returns it, otherwise
>            # returns None.
>            type = self.obj.analyse_as_extension_type(env)
> -        if type:
> +        if type and type.scope:
>                entry = type.scope.lookup_here(self.attribute)
>                if entry and entry.is_cmethod:
>                    if type.is_builtin_type:
>
> It fixes CompilerCrash (None does not have "lookup_here" method)
> that I have observed on two occasions:
> 1) cdef class Name; cimport Name; Name.attr
> 2) from X cimport Name; Name.attr  # cimport_from_pyx is active, Name is a
> class with errors
>
> Makes me wonder if ErrorScope should be introduced to avoid None scope
> checks.
>
>
> Best regards,
> Nikita Nemkin
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