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classification
Title: test_gdb: attempt to dereference a generic pointer
Type: behavior Stage: resolved
Components: Tests Versions: Python 3.3
process
Status: closed Resolution: fixed
Dependencies: Superseder:
Assigned To: Nosy List: loewis, pitrou, python-dev, skrah, vstinner
Priority: normal Keywords:

Created on 2011-10-08 06:54 by skrah, last changed 2022-04-11 14:57 by admin. This issue is now closed.

Messages (5)
msg145161 - (view) Author: Stefan Krah (skrah) * (Python committer) Date: 2011-10-08 06:54
The Fedora bot fails since yesterday:


Breakpoint 1, builtin_id (self=<module at remote 0x7ffff7f6fc90>, v=Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.krah-fedora/build/python-gdb.py", line 1329, in to_string
    return pyop.get_truncated_repr(MAX_OUTPUT_LEN)
  File "/home/buildbot/buildarea/3.x.krah-fedora/build/python-gdb.py", line 213, in get_truncated_repr
    self.write_repr(out, set())
  File "/home/buildbot/buildarea/3.x.krah-fedora/build/python-gdb.py", line 1199, in write_repr
    proxy = self.proxyval(visited)
  File "/home/buildbot/buildarea/3.x.krah-fedora/build/python-gdb.py", line 1166, in proxyval
    Py_UNICODEs = [int(field_str[i]) for i in safe_range(field_length)]
RuntimeError: Attempt to dereference a generic pointer.
) at Python/bltinmodule.c:927
927	    return PyLong_FromVoidPtr(v);
#0  builtin_id (self=<module at remote 0x7ffff7f6fc90>, v=Traceback (most recent call last):
  File "/home/buildbot/buildarea/3.x.krah-fedora/build/python-gdb.py", line 1329, in to_string
    return pyop.get_truncated_repr(MAX_OUTPUT_LEN)
  File "/home/buildbot/buildarea/3.x.krah-fedora/build/python-gdb.py", line 213, in get_truncated_repr
    self.write_repr(out, set())
  File "/home/buildbot/buildarea/3.x.krah-fedora/build/python-gdb.py", line 1199, in write_repr
    proxy = self.proxyval(visited)
  File "/home/buildbot/buildarea/3.x.krah-fedora/build/python-gdb.py", line 1166, in proxyval
    Py_UNICODEs = [int(field_str[i]) for i in safe_range(field_length)]
RuntimeError: Attempt to dereference a generic pointer.
) at Python/bltinmodule.c:927
#1  0x00000000004b667f in call_function (pp_stack=0x7fffffffd6e8, oparg=1) at Python/ceval.c:3988
#2  0x00000000004b0787 in PyEval_EvalFrameEx (f=Frame 0x7ffff7f409c0, for file <string>, line 1, in <module> (), throwflag=0) at Python/ceval.c:2625
#3  0x00000000004b44ca in PyEval_EvalCodeEx (_co=<code at remote 0x7ffff7f3c880>, globals={'__builtins__': <module at remote 0x7ffff7f6fc90>, '__name__': '__main__', '__doc__': None, '__package__': None}, locals={'__builtins__': <module at remote 0x7ffff7f6fc90>, '__name__': '__main__', '__doc__': None, '__package__': None}, args=0x0, argcount=0, kws=0x0, kwcount=0, defs=0x0, defcount=0, kwdefs=0x0, closure=0x0) at Python/ceval.c:3375
#4  0x00000000004a4668 in PyEval_EvalCode (co=<code at remote 0x7ffff7f3c880>, globals={'__builtins__': <module at remote 0x7ffff7f6fc90>, '__name__': '__main__', '__doc__': None, '__package__': None}, locals={'__builtins__': <module at remote 0x7ffff7f6fc90>, '__name__': '__main__', '__doc__': None, '__package__': None}) at Python/ceval.c:770
#5  0x00000000004edc20 in run_mod (mod=0x9b0560, filename=0x619622 "<string>", globals={'__builtins__': <module at remote 0x7ffff7f6fc90>, '__name__': '__main__', '__doc__': None, '__package__': None}, locals={'__builtins__': <module at remote 0x7ffff7f6fc90>, '__name__': '__main__', '__doc__': None, '__package__': None}, flags=0x7fffffffe3c0, arena=0x92e070) at Python/pythonrun.c:1795
#6  0x00000000004ed91e in PyRun_StringFlags (str=0x7ffff10e1418 "id('\\U0001d121')\n", start=257, globals={'__builtins__': <module at remote 0x7ffff7f6fc90>, '__name__': '__main__', '__doc__': None, '__package__': None}, locals={'__builtins__': <module at remote 0x7ffff7f6fc90>, '__name__': '__main__', '__doc__': None, '__package__': None}, flags=0x7fffffffe3c0) at Python/pythonrun.c:1729
#7  0x00000000004ebfb6 in PyRun_SimpleStringFlags (command=0x7ffff10e1418 "id('\\U0001d121')\n", flags=0x7fffffffe3c0) at Python/pythonrun.c:1302
#8  0x000000000050b41f in run_command (command=0x8e0500 L"id('\\U0001d121')\n", cf=0x7fffffffe3c0) at Modules/main.c:260
#9  0x000000000050bf70 in Py_Main (argc=4, argv=0x7ffff7faf040) at Modules/main.c:634
#10 0x0000000000416e97 in main (argc=4, argv=0x7fffffffe5a8) at ./Modules/python.c:59
msg145175 - (view) Author: Antoine Pitrou (pitrou) * (Python committer) Date: 2011-10-08 16:21
Following patch seems to fix it:

diff --git a/Tools/gdb/libpython.py b/Tools/gdb/libpython.py
--- a/Tools/gdb/libpython.py
+++ b/Tools/gdb/libpython.py
@@ -1152,7 +1152,7 @@ class PyUnicodeObjectPtr(PyObjectPtr):
                     field_str = field_str.cast(_type_unsigned_char_ptr)
                 elif repr_kind == 2:
                     field_str = field_str.cast(_type_unsigned_short_ptr)
-                elif repr_kind == 3:
+                elif repr_kind == 4:
                     field_str = field_str.cast(_type_unsigned_int_ptr)
         else:
             # Python 3.2 and earlier
msg145177 - (view) Author: Roundup Robot (python-dev) (Python triager) Date: 2011-10-08 17:37
New changeset ef1f0434c79c by Antoine Pitrou in branch 'default':
Fix test_gdb following the small unicode struct change in c25262e97304 (issue #13130)
http://hg.python.org/cpython/rev/ef1f0434c79c
msg145178 - (view) Author: Antoine Pitrou (pitrou) * (Python committer) Date: 2011-10-08 17:42
Let's wait for the buildbots.
msg145180 - (view) Author: Antoine Pitrou (pitrou) * (Python committer) Date: 2011-10-08 18:21
Seems to have cleared the buildbot failures.
History
Date User Action Args
2022-04-11 14:57:22adminsetgithub: 57339
2011-10-08 18:21:32pitrousetstatus: pending -> closed

messages: + msg145180
2011-10-08 17:42:03pitrousetstatus: open -> pending
resolution: fixed
messages: + msg145178

stage: needs patch -> resolved
2011-10-08 17:37:05python-devsetnosy: + python-dev
messages: + msg145177
2011-10-08 16:21:03pitrousetnosy: + pitrou
messages: + msg145175
2011-10-08 06:54:37skrahcreate