From dfc12edbca2df81f13bbb48351b1aedb8773f885 Mon Sep 17 00:00:00 2001 From: Christian Heimes Date: Thu, 31 Jan 2008 15:16:38 +0000 Subject: [PATCH] Fixed multiple reinitialization of the Python interpreter. The small int list in longobject.c has caused a seg fault during the third finalization. --- Misc/NEWS | 3 +++ Objects/longobject.c | 59 +++++++++++++++++++++++++++----------------- 2 files changed, 39 insertions(+), 23 deletions(-) diff --git a/Misc/NEWS b/Misc/NEWS index 6b7b69296c2..a9da8b6ae21 100644 --- a/Misc/NEWS +++ b/Misc/NEWS @@ -12,6 +12,9 @@ What's New in Python 3.0a3? Core and Builtins ----------------- +- Fixed multiple reinitialization of the Python interpreter. The small int + list in longobject.c has caused a seg fault during the third finalization. + - Issue #1973: bytes.fromhex('') raises SystemError - Issue #1771: remove cmp parameter from sorted() and list.sort() diff --git a/Objects/longobject.c b/Objects/longobject.c index 18f158a78a4..fe9bf8e6e10 100644 --- a/Objects/longobject.c +++ b/Objects/longobject.c @@ -3705,17 +3705,34 @@ int _PyLong_Init(void) { #if NSMALLNEGINTS + NSMALLPOSINTS > 0 - int ival; + int ival, size; PyLongObject *v = small_ints; - for (ival = -NSMALLNEGINTS; ival < 0; ival++, v++) { - PyObject_INIT(v, &PyLong_Type); - Py_SIZE(v) = -1; - v->ob_digit[0] = -ival; - } - for (; ival < NSMALLPOSINTS; ival++, v++) { - PyObject_INIT(v, &PyLong_Type); - Py_SIZE(v) = ival ? 1 : 0; - v->ob_digit[0] = ival; + + for (ival = -NSMALLNEGINTS; ival < NSMALLPOSINTS; ival++, v++) { + size = (ival < 0) ? -1 : ((ival == 0) ? 0 : 1); + if (Py_TYPE(v) == &PyLong_Type) { + /* The element is already initialized, most likely + * the Python interpreter was initialized before. + */ + /* _Py_NewReference((PyObject*)v); + * XXX: It sets the ref count to 1 but it may be + * larger. Emulate new reference w/o setting refcnt + * to 1. + */ + PyObject* op = (PyObject*)v; + _Py_INC_REFTOTAL; + op->ob_refcnt = (op->ob_refcnt < 1) ? 1 : op->ob_refcnt; + _Py_AddToAllObjects(op, 1); + _Py_INC_TPALLOCS(op); + + assert(Py_SIZE(op) == size); + assert(v->ob_digit[0] == abs(ival)); + } + else { + PyObject_INIT(v, &PyLong_Type); + } + Py_SIZE(v) = size; + v->ob_digit[0] = abs(ival); } #endif return 1; @@ -3724,19 +3741,15 @@ _PyLong_Init(void) void PyLong_Fini(void) { -#if 0 - int i; - /* This is currently not needed; the small integers - are statically allocated */ + /* Integers are currently statically allocated. Py_DECREF is not + needed, but Python must forget about the reference or multiple + reinitializations will fail. */ #if NSMALLNEGINTS + NSMALLPOSINTS > 0 - PyIntObject **q; - - i = NSMALLNEGINTS + NSMALLPOSINTS; - q = small_ints; - while (--i >= 0) { - Py_XDECREF(*q); - *q++ = NULL; - } -#endif + int i; + PyLongObject *v = small_ints; + for (i = 0; i < NSMALLNEGINTS + NSMALLPOSINTS; i++, v++) { + _Py_DEC_REFTOTAL; + _Py_ForgetReference((PyObject*)v); + } #endif }