Hi, the Cython and PyPy projects are currently working on getting Cython implemented extensions to build and run in PyPy, interfacing at the C-API level for now. One problem we encountered was that there is currently no "abstract" way to access tstate->exc_type and friends, i.e. the last exception that was caught, aka. sys.exc_info(). Apparently, PyPy stores them at a frame level, whereas CPython makes them available in thread local storage as bare struct fields. Even if PyPy put them there on request, any changes to these fields would pass unnoticed. And Cython needs to set them in order to properly implement the semantics of a try-except statement (and in some other places where exception state is scoped). When compiling for PyPy, Cython therefore needs a way to tell PyPy about any changes. For the tstate->curexc_* fields, there are the two functions PyErr_Fetch() and PyErr_Restore(). Could we have two similar "official" functions for the exc_* fields? Maybe PyErr_FetchLast() and PyErr_RestoreLast()? Note that Cython would not have a reason to actually use them in CPython, and it should be uncommon for non-Cython extension modules to care about the exc_* fields at all. So these functions won't be of much use if actually implemented in CPython (although I wouldn't mind doing that). The question is just if we could have two officially named functions that PyPy (and maybe other Pythons) could implement in order to access the last raised exception in a way that does not depend on implementation details. Stefan