seterror() uses a char array and a pointer to the current position in
that array. Use snprintf() and compute the amount of space left in
the buffer based on the current pointer position.
If it returns -1 (which indicates overflow on old Linux platforms and
perhaps on Windows) or size greater than buffer, write a message
indicating that the previous message was truncated.
com_arglist(), symtable_check_unoptimized(), symtable_params(),
symtable_global(), symtable_list_comprehension():
Conversion of sprintf() to PyOS_snprintf() for buffer overrun
avoidance.
PyEval_EvalCodeEx(): increment tstate->recursion_depth around the
decref of the frame, because the C stack for this call is still in
use and the decref can lead to __del__ methods getting called.
While this gives tstate->recursion_depth a value proportional to the
depth of the C stack (instead of a small constant no matter how
deeply __del__s recurse), it's not enough to stop the reported crash
when using the default recursion limit on Windows.
Bugfix candidate.
Bugfix candidate.
tb_displayline(): the sprintf format was choking off the file name, but
used plain %s for the function name (which can be arbitrarily long).
Limit both to 500 chars max.
uninitialized memory reads reported in bug #478001.
Note that this doesn't address the following larger issues:
- Error conditions are not documented for PyOS_*sig() in the C API.
- Nothing that actually calls PyOS_*sig() in the core interpreter and
extension modules actually /checks/ the return value of the call.
Fixing those is left as an exercise for a later day.
This patch boosts performance for comparing identical string object
by some 20% on my machine while not causing any noticable slow-down
for other operations (according to tests done with pybench).