When a body of C extensions needs to be ported from python <3.8 to 3.8, one of the issues one might run into is improperly defined methods in a C extension, which results in SystemErrors stating:

>>> SystemError: bad call flags

This new behavior was added as part of Issue # 33012.

While the issues definitely need to be resolved in the C extensions, where to start is not completely clear. I had to put `printfs` in PyCFunction_NewEx and PyDescr_NewMethod to track down the issues, e.g.,

>>> printf("method name: %s\n", method->ml_name);

While this might be misleading for duplicate method definitions, it definitely helps narrow down the offending code.

Adding the method name to the SystemError would be a big step in the right direction in terms of making it easier to resolve these issues.

PS I realize that this might be masked by casting PyCFunction on methods or by not using gcc 8+, but I'd argue that C extensions need to have developer issues like this be clearer to the end-reader.