New GitHub issue #118990 from christian-heusel:<br>
<hr>
<pre>
# Crash report
### What happened?
This is a follow-up on another bug report to the diffoscope program, after we have concluded that its is not the program but the interpreter that crashes: https://salsa.debian.org/reproducible-builds/diffoscope/-/issues/371
The other bug report also has some background information and stacktraces that occur with the original diffoscope issue.
The following snippet (with [`a.pyc`](https://salsa.debian.org/reproducible-builds/diffoscope/uploads/f29fce68d768674b06329675a58ee5cd/a.pyc)) seems to crash the python interpreter for me:
```python
from diffoscope.comparators.python import parse_pyc
len(list(parse_pyc(open("a.pyc", "rb"))))
```
This gets me the following traceback:
```
(gdb) bt full
#0 __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44
tid = <optimized out>
ret = 0
pd = <optimized out>
old_mask = {__val = {140737488344448}}
ret = <optimized out>
#1 0x00007ffff76a8eb3 in __pthread_kill_internal (threadid=<optimized out>, signo=6) at pthread_kill.c:78
No locals.
#2 0x00007ffff7650a30 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26
ret = <optimized out>
#3 0x00007ffff76384c3 in __GI_abort () at abort.c:79
save_stage = 1
act = {__sigaction_handler = {sa_handler = 0x20, sa_sigaction = 0x20}, sa_mask = {__val = {563003392984950430, 140737338523248, 140737347523616,
140737338523408, 0, 140737335247376, 140737334969392, 8, 93824994291376, 140737338523248, 140737347523616, 15, 5, 140737333430000,
140737334971376, 16}}, sa_flags = -1259926528, sa_restorer = 0xf}
#4 0x00007ffff7639354 in __libc_message_impl (fmt=fmt@entry=0x7ffff77c22ea "%s\n") at ../sysdeps/posix/libc_fatal.c:132
ap = {{gp_offset = 16, fp_offset = 32767, overflow_arg_area = 0x7fffffffd7b0, reg_save_area = 0x7fffffffd740}}
fd = 2
iov = {{iov_base = 0x7ffff77bffe1, iov_len = 28}, {iov_base = 0x7ffff77c22ec, iov_len = 1}, {iov_base = 0x7ffff711be70, iov_len = 140737347523616}, {
iov_base = 0x5555556bceb0, iov_len = 40}, {iov_base = 0x555555817c50, iov_len = 140737333753808}, {iov_base = 0x80, iov_len = 93824995122304}, {
iov_base = 0x7f, iov_len = 140737347269691}}
iovcnt = <optimized out>
total = <optimized out>
cp = <optimized out>
#5 0x00007ffff76b3085 in malloc_printerr (str=str@entry=0x7ffff77bffe1 "corrupted size vs. prev_size") at malloc.c:5772
No locals.
#6 0x00007ffff76b3c16 in unlink_chunk (p=p@entry=0x5555557f5fa0, av=0x7ffff77f6ac0 <main_arena>) at malloc.c:1611
fd = <optimized out>
bk = <optimized out>
#7 0x00007ffff76b3e6c in _int_free_create_chunk (av=av@entry=0x7ffff77f6ac0 <main_arena>, p=p@entry=0x5555557f5d10, size=size@entry=656,
nextchunk=nextchunk@entry=0x5555557f5fa0, nextsize=nextsize@entry=656) at malloc.c:4721
nextinuse = <optimized out>
bck = <optimized out>
fwd = <optimized out>
#8 0x00007ffff76b51ca in _int_free_merge_chunk (av=0x7ffff77f6ac0 <main_arena>, p=0x5555557f5d10, size=656) at malloc.c:4700
nextchunk = 0x5555557f5fa0
nextsize = 656
#9 0x00007ffff76b53ea in _int_free (av=<optimized out>, p=p@entry=0x5555557f5d10, have_lock=<optimized out>, have_lock@entry=0) at malloc.c:4646
size = <optimized out>
fb = <optimized out>
#10 0x00007ffff76b7dae in __GI___libc_free (mem=mem@entry=0x5555557f5d20) at malloc.c:3398
ar_ptr = <optimized out>
p = 0x5555557f5d10
err = 0
#11 0x00007ffff79adb0c in _PyMem_RawFree (_unused_ctx=<optimized out>, ptr=0x5555557f5d20) at Objects/obmalloc.c:73
No locals.
#12 PyMem_RawFree (ptr=0x5555557f5d20) at Objects/obmalloc.c:685
No locals.
#13 _PyObject_Free (p=0x5555557f5d20, ctx=<optimized out>) at Objects/obmalloc.c:1853
state = 0x7ffff7dc6140 <_PyRuntime+80352>
state = <optimized out>
#14 PyObject_Free (ptr=0x5555557f5d20) at Objects/obmalloc.c:830
No locals.
#15 code_dealloc (co=0x5555557f5d20) at Objects/codeobject.c:1745
No locals.
#16 0x00007ffff799db11 in Py_DECREF (op=<optimized out>) at ./Include/object.h:705
No locals.
#17 func_dealloc (op=0x7ffff6b15260) at Objects/funcobject.c:856
No locals.
#18 0x00007ffff79827a0 in _Py_Dealloc (op=<optimized out>) at Objects/object.c:2625
type = <optimized out>
dealloc = <optimized out>
#19 Py_DECREF (op=<optimized out>) at ./Include/object.h:705
No locals.
#20 Py_XDECREF (op=<optimized out>) at ./Include/object.h:798
No locals.
#21 free_keys_object (interp=0x7ffff7dc51c8 <_PyRuntime+76392>, keys=0x55555581bbb0) at Objects/dictobject.c:673
entries = <optimized out>
i = 76
n = <optimized out>
state = <optimized out>
#22 0x00007ffff7a6e0ab in type_clear (type=0x55555581a8c0) at Objects/typeobject.c:5295
dict = <optimized out>
#23 0x00007ffff798fc7a in delete_garbage (old=0x7ffff7dc5280 <_PyRuntime+76576>, collectable=0x7fffffffd9c0, gcstate=0x7ffff7dc5238 <_PyRuntime+76504>,
tstate=0x7ffff7e22ae8 <_PyRuntime+459656>) at Modules/gcmodule.c:1029
clear = <optimized out>
gc = <optimized out>
op = 0x55555581a8c0
#24 gc_collect_main (tstate=tstate@entry=0x7ffff7e22ae8 <_PyRuntime+459656>, generation=generation@entry=2, n_collected=n_collected@entry=0x0,
n_uncollectable=n_uncollectable@entry=0x0, nofail=nofail@entry=1) at Modules/gcmodule.c:1303
i = <optimized out>
m = 3913
n = 0
young = 0x7ffff7dc5280 <_PyRuntime+76576>
old = <optimized out>
unreachable = {_gc_next = 140737488345520, _gc_prev = 140737488345520}
finalizers = {_gc_next = 140737488345504, _gc_prev = 140737488345504}
gc = <optimized out>
t1 = 0
gcstate = 0x7ffff7dc5238 <_PyRuntime+76504>
final_unreachable = {_gc_next = 93824995141808, _gc_prev = 140737332415728}
stats = <optimized out>
#25 0x00007ffff7a759fc in _PyGC_CollectNoFail (tstate=tstate@entry=0x7ffff7e22ae8 <_PyRuntime+459656>) at Modules/gcmodule.c:2135
gcstate = 0x7ffff7dc5238 <_PyRuntime+76504>
n = <optimized out>
#26 0x00007ffff7a74ab4 in finalize_modules (tstate=tstate@entry=0x7ffff7e22ae8 <_PyRuntime+459656>) at Python/pylifecycle.c:1588
interp = <optimized out>
modules = 0x7ffff7190200
verbose = <optimized out>
weaklist = 0x7ffff7191200
#27 0x00007ffff7a5e406 in Py_FinalizeEx () at Python/pylifecycle.c:1889
status = <optimized out>
runtime = 0x7ffff7db2760 <_PyRuntime>
tstate = <optimized out>
malloc_stats = <optimized out>
#28 0x00007ffff7a6ccf2 in Py_RunMain () at Modules/main.c:711
exitcode = 0
#29 0x00007ffff7a28fab in Py_BytesMain (argc=<optimized out>, argv=<optimized out>) at Modules/main.c:763
args = {argc = 1, use_bytes_argv = 1, bytes_argv = 0x7fffffffde58, wchar_argv = 0x0}
#30 0x00007ffff7639c88 in __libc_start_call_main (main=main@entry=0x555555555120 <main>, argc=argc@entry=1, argv=argv@entry=0x7fffffffde58)
at ../sysdeps/nptl/libc_start_call_main.h:58
self = <optimized out>
result = <optimized out>
unwind_buf = {cancel_jmp_buf = {{jmp_buf = {140737488346712, 6779890582023430464, 1, 0, 140737354125312, 93824992247232, 6779890582008750400,
6779909378961826112}, mask_was_saved = 0}}, priv = {pad = {0x0, 0x0, 0x1, 0x7fffffffde50}, data = {prev = 0x0, cleanup = 0x0,
canceltype = 1}}}
not_first_call = <optimized out>
#31 0x00007ffff7639d4c in __libc_start_main_impl (main=0x555555555120 <main>, argc=1, argv=0x7fffffffde58, init=<optimized out>, fini=<optimized out>,
rtld_fini=<optimized out>, stack_end=0x7fffffffde48) at ../csu/libc-start.c:360
No locals.
#32 0x0000555555555045 in _start ()
No symbol table info available.
```
I have also looked at [previous issues](https://github.com/python/cpytho
</pre>
<hr>
<a href="https://github.com/python/cpython/issues/118990">View on GitHub</a>
<p>Labels: type-crash</p>
<p>Assignee: </p>