* python/py-breakpoint.c (bppy_set_condition): New comment.
* python/py-cmd.c (cmdpy_function): Call also gdbpy_print_stack for
failed PyUnicode_Decode.
(cmdpy_completer): Skip element for failed
python_string_to_host_string.
(cmdpy_init): Return -1 on failed python_string_to_host_string.
* python/py-frame.c (frapy_read_var): Extend the function comment.
* python/py-function.c (fnpy_init): Return -1 on failed
python_string_to_host_string.
* python/py-inferior.c (infpy_read_memory, infpy_write_memory): Extend
the function comment.
(infpy_search_memory): Extend the function comment. Remove the
PyErr_SetString call on already set error state.
* python/py-param.c (set_parameter_value): Extend the function
comment. Return -1 on failed python_string_to_host_string, twice.
(set_attr): Extend the function comment.
(compute_enum_values): Extend the function comment. New variable
back_to. Protect self->enumeration by BACK_TO cleanups. Return 0 on
failed python_string_to_host_string.
(get_doc_string): Call gdbpy_print_stack on failed
python_string_to_host_string.
(parmpy_init): Extend the function comment.
* python/py-prettyprint.c (pretty_print_one_value): Likewise.
(gdbpy_get_display_hint, print_children): Call gdbpy_print_stack on
failed python_string_to_host_string.
* python/py-value.c (valpy_new, valpy_getitem, valpy_call)
(valpy_binop, valpy_richcompare): Extend the function comment.
* python/python.c
(struct python_env) <error_type, error_value, error_traceback>: New
fields.
(restore_python_env): Handle PyErr_Occurred. Call PyErr_Restore.
(ensure_python_env): Call PyErr_Fetch.
* varobj.c (update_dynamic_varobj_children): Call gdbpy_print_stack on
failed convert_value_from_python.
(value_get_print_value): Call gdbpy_print_stack on failed
python_string_to_target_python_string.
gdb/testsuite/
* gdb.python/py-error.exp: New file.
* gdb.python/py-error.py: New file.
