Segfault on repr of instances of _ItemsView, _KeysView or _ValuesView #1161
Description
Directly building an instance of _ItemsView, _KeysView or _ValuesView and calling repr on it will lead to a segfault. Instances created by calling the corresponding methods(e.g. MultiDict(a=1).keys()) don't suffer from this.
>>> import multidict
>>> repr(multidict._ItemsView())
Program received signal SIGSEGV, Segmentation fault.
0x00007ffff6d11494 in pair_list_repr (list=0x10, name=0x7ffff6aa5940, show_keys=true,
show_values=true) at multidict/_multilib/pair_list.h:1517#0 0x00007ffff6d11494 in pair_list_repr (list=0x10, name=0x7ffff6aa5940, show_keys=true,
show_values=true) at multidict/_multilib/pair_list.h:1517
#1 0x00007ffff6d11b4d in multidict_itemsview_repr (self=0x7ffff6c443d0)
at multidict/_multilib/views.h:187
#2 0x00005555556cb1c9 in PyObject_Repr (v=v@entry=0x7ffff6c443d0) at Objects/object.c:765
#3 0x0000555555691073 in PyFile_WriteObject (v=v@entry=0x7ffff6c443d0, f=f@entry=0x7ffff7475400,
flags=flags@entry=0) at Objects/fileobject.c:120
#4 0x0000555555835aa0 in sys_displayhook (module=<optimized out>, o=o@entry=0x7ffff6c443d0)
at ./Python/sysmodule.c:825
#5 0x00005555556c6490 in cfunction_vectorcall_O (func=0x7ffff75a24b0, args=<optimized out>,
nargsf=<optimized out>, kwnames=<optimized out>) at Objects/methodobject.c:512
#6 0x00005555556746fa in _PyObject_VectorcallTstate (tstate=0x555555b604c0 <_PyRuntime+299040>,
callable=callable@entry=0x7ffff75a24b0, args=args@entry=0x7fffffffcd68,
nargsf=nargsf@entry=9223372036854775809, kwnames=kwnames@entry=0x0)
at ./Include/internal/pycore_call.h:168
#7 0x0000555555674826 in PyObject_CallOneArg (func=func@entry=0x7ffff75a24b0,
arg=arg@entry=0x7ffff6c443d0) at Objects/call.c:395
#8 0x0000555555807788 in print_expr (_unused_ignored=<optimized out>, value=0x7ffff6c443d0)
at Python/intrinsics.c:33
#9 0x00005555557a5098 in _PyEval_EvalFrameDefault (tstate=0x555555b604c0 <_PyRuntime+299040>,
frame=0x7ffff7fb05f0, throwflag=0) at Python/generated_cases.c.h:1376
#10 0x00005555557b4b05 in _PyEval_EvalFrame (
tstate=tstate@entry=0x555555b604c0 <_PyRuntime+299040>, frame=<optimized out>,
throwflag=throwflag@entry=0) at ./Include/internal/pycore_ceval.h:119
#11 0x00005555557b4c34 in _PyEval_Vector (tstate=tstate@entry=0x555555b604c0 <_PyRuntime+299040>,
func=func@entry=0x7ffff6fa9d90, locals=locals@entry=0x7ffff7463d70, args=args@entry=0x0,
argcount=argcount@entry=0, kwnames=kwnames@entry=0x0) at Python/ceval.c:1816
#12 0x00005555557b4cf7 in PyEval_EvalCode (co=co@entry=0x7ffff6bca460,
globals=globals@entry=0x7ffff7463d70, locals=locals@entry=0x7ffff7463d70)
at Python/ceval.c:604
#13 0x00005555557988e1 in builtin_exec_impl (module=module@entry=0x7ffff75a6930,
source=0x7ffff6bca460, globals=0x7ffff7463d70, locals=0x7ffff7463d70, closure=0x0)
at Python/bltinmodule.c:1143
#14 0x0000555555798a44 in builtin_exec (module=0x7ffff75a6930, args=<optimized out>,
args@entry=0x7ffff7fb05e0, nargs=nargs@entry=2, kwnames=kwnames@entry=0x0)
at Python/clinic/bltinmodule.c.h:556multidict.__version__
'6.4.3'
Python versions:
Python 3.13.3+ (heads/3.13:fdcaaad1cc7, Apr 27 2025, 10:17:23) [GCC 14.2.0] on linux