bpo-39114: Fix tracing of except handlers with name binding (GH-17769)

When producing the bytecode of exception handlers with name binding (like `except Exception as e`) we need to produce a try-finally block to make sure that the name is deleted after the handler is executed to prevent cycles in the stack frame objects. The bytecode associated with this try-finally block does not have source lines associated and it was causing problems when the tracing functionality was running over it.
This commit is contained in:
Pablo Galindo 2020-01-02 11:38:44 +00:00 committed by GitHub
parent 149175c6df
commit 04ec7a1f7a
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3 changed files with 50 additions and 1 deletions

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@ -481,6 +481,51 @@ class TraceTestCase(unittest.TestCase):
[(0, 'call'),
(1, 'line')])
def test_18_except_with_name(self):
def func():
try:
try:
raise Exception
except Exception as e:
raise
x = "Something"
y = "Something"
except Exception:
pass
self.run_and_compare(func,
[(0, 'call'),
(1, 'line'),
(2, 'line'),
(3, 'line'),
(3, 'exception'),
(4, 'line'),
(5, 'line'),
(8, 'line'),
(9, 'line'),
(9, 'return')])
def test_19_except_with_finally(self):
def func():
try:
try:
raise Exception
finally:
y = "Something"
except Exception:
b = 23
self.run_and_compare(func,
[(0, 'call'),
(1, 'line'),
(2, 'line'),
(3, 'line'),
(3, 'exception'),
(5, 'line'),
(6, 'line'),
(7, 'line'),
(7, 'return')])
class SkipLineEventsTraceTestCase(TraceTestCase):
"""Repeat the trace tests, but with per-line events skipped"""

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@ -0,0 +1,2 @@
Fix incorrent line execution reporting in trace functions when tracing
exception handlers with name binding. Patch by Pablo Galindo.

View File

@ -3610,7 +3610,9 @@ exception_unwind:
PUSH(val);
PUSH(exc);
JUMPTO(handler);
if (_Py_TracingPossible(ceval)) {
if (_Py_TracingPossible(ceval) &&
((f->f_lasti < instr_lb || f->f_lasti >= instr_ub) ||
!(f->f_lasti == instr_lb || f->f_lasti < instr_prev))) {
/* Make sure that we trace line after exception */
instr_prev = INT_MAX;
}