Calling built-in locals() and globals() in C++ leads to SystemError

[ghost]

BPO	35536
Nosy	@benjaminp

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = None
created_at = <Date 2018-12-19.14:54:20.890>
labels = ['type-bug', 'library']
title = 'Calling built-in locals() and globals() in C++ leads to SystemError'
updated_at = <Date 2018-12-20.06:03:51.696>
user = None

bugs.python.org fields:

activity = <Date 2018-12-20.06:03:51.696>
actor = '\xd0\x9d\xd0\xb8\xd0\xba\xd0\xb8\xd1\x82\xd0\xb0 \xd0\xa1\xd0\xb8\xd1\x80\xd0\xb3\xd0\xb8\xd0\xb5\xd0\xbd\xd0\xba\xd0\xbe'
assignee = 'none'
closed = False
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2018-12-19.14:54:20.890>
creator = '\xd0\x9d\xd0\xb8\xd0\xba\xd0\xb8\xd1\x82\xd0\xb0 \xd0\xa1\xd0\xb8\xd1\x80\xd0\xb3\xd0\xb8\xd0\xb5\xd0\xbd\xd0\xba\xd0\xbe'
dependencies = []
files = []
hgrepos = []
issue_num = 35536
keywords = []
message_count = 3.0
messages = ['332144', '332175', '332178']
nosy_count = 2.0
nosy_names = ['benjamin.peterson', '\xd0\x9d\xd0\xb8\xd0\xba\xd0\xb8\xd1\x82\xd0\xb0 \xd0\xa1\xd0\xb8\xd1\x80\xd0\xb3\xd0\xb8\xd0\xb5\xd0\xbd\xd0\xba\xd0\xbe']
pr_nums = []
priority = 'normal'
resolution = None
stage = None
status = 'open'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue35536'
versions = ['Python 2.7', 'Python 3.6']

[ghost]

System:
Distributor ID: Ubuntu
Description: Ubuntu 18.04.1 LTS
Release: 18.04
Codename: bionic
Arch: x86_64

Compilier:
g++ (Ubuntu 7.3.0-27ubuntu1~18.04) 7.3.0

Python versions:
Python 3.6.7-1
Python 2.7.15rc1

Description:
This C++ code:

    PyObject* pBuiltin = PyImport_ImportModule("builtins");
    PyObject* py_globals_fun = PyObject_GetAttrString(pBuiltin,"locals");
    PyObject* globals = PyObject_CallObject(py_globals_fun, NULL);

produces "SystemError: frame does not exist".
For function "globals" output is "SystemError: returned NULL without
setting an error". For python2 this code produces similar errors (descriptions
of error little different).

Another functions with arguments, like "abs", works fine.
And calling function with optional argument, like "int", "float"
works with this code (with null parameter) without problem.

[benjaminp]

What behavior are you expecting? If there isn't any Python code in the callback, globals() and locals() are meaningless.

[ghost]

I run some Python code before this moment, so I expect, that globals variable will be a PyDictObject with results of 'globals()' command: '__name__', '__doc__', global variables, etc.