Fix:

* crashes on memory allocation failure found with failmalloc
 * memory leaks found with valgrind
 * compiler warnings in opt mode which would lead to invalid memory reads
 * problem using wrong name in decimal module reported by pychecker

Update the valgrind suppressions file with new leaks that are small/one-time
leaks we don't care about (ie, they are too hard to fix).

TBR=barry
TESTED=./python -E -tt ./Lib/test/regrtest.py -uall (both debug and opt modes)
  in opt mode:
  valgrind -q --leak-check=yes --suppressions=Misc/valgrind-python.supp \
    ./python -E -tt ./Lib/test/regrtest.py -uall,-bsddb,-compiler \
                        -x test_logging test_ssl test_multiprocessing
  valgrind -q --leak-check=yes --suppressions=Misc/valgrind-python.supp \
    ./python -E -tt ./Lib/test/regrtest.py test_multiprocessing
  for i in `seq 1 4000` ; do
    LD_PRELOAD=~/local/lib/libfailmalloc.so FAILMALLOC_INTERVAL=$i \
        ./python -c pass
  done

At least some of these fixes should probably be backported to 2.5.

Lib/decimal.py

@@ -5061,7 +5061,7 @@ def _dlog10(c, e, p):
         log_tenpower = f*M # exact
     else:
         log_d = 0  # error < 2.31
-        log_tenpower = div_nearest(f, 10**-p) # error < 0.5
+        log_tenpower = _div_nearest(f, 10**-p) # error < 0.5
 
     return _div_nearest(log_tenpower+log_d, 100)
 

Misc/NEWS

@@ -12,6 +12,14 @@ What's New in Python 2.6 release candidate 1?
 Core and Builtins
 -----------------
 
+- Fix crashes on memory allocation failure found with failmalloc.
+
+- Fix memory leaks found with valgrind and update suppressions file.
+
+- Fix compiler warnings in opt mode which would lead to invalid memory reads.
+
+- Fix problem using wrong name in decimal module reported by pychecker.
+
 - Issue #3642: Changed type of numarenas from uint to size_t
   in order to silence a compilier warning on 64bit OSes.
 

Misc/valgrind-python.supp

@@ -46,6 +46,39 @@
 #    Will need to fix that.
 #
 
+{
+   Suppress leaking the GIL.  Happens once per process, see comment in ceval.c.
+   Memcheck:Leak
+   fun:malloc
+   fun:PyThread_allocate_lock
+   fun:PyEval_InitThreads
+}
+
+{
+   Suppress leaking the GIL after a fork.
+   Memcheck:Leak
+   fun:malloc
+   fun:PyThread_allocate_lock
+   fun:PyEval_ReInitThreads
+}
+
+{
+   Suppress leaking the autoTLSkey.  This looks like it shouldn't leak though.
+   Memcheck:Leak
+   fun:malloc
+   fun:PyThread_create_key
+   fun:_PyGILState_Init
+   fun:Py_InitializeEx
+   fun:Py_Main
+}
+
+{
+   Hmmm, is this a real leak or like the GIL?
+   Memcheck:Leak
+   fun:malloc
+   fun:PyThread_ReInitTLS
+}
+
 {
    Handle PyMalloc confusing valgrind (possibly leaked)
    Memcheck:Leak

Modules/_ctypes/stgdict.c

@@ -416,6 +416,7 @@ StructUnionType_update_stgdict(PyObject *type, PyObject *fields, int isStruct)
 		ffi_ofs = 0;
 	}
 
+	assert(stgdict->format == NULL);
 	if (isStruct && !isPacked) {
 		stgdict->format = alloc_format_string(NULL, "T{");
 	} else {
@@ -539,7 +540,9 @@ StructUnionType_update_stgdict(PyObject *type, PyObject *fields, int isStruct)
 #undef realdict
 
 	if (isStruct && !isPacked) {
+		char *ptr = stgdict->format;
 		stgdict->format = alloc_format_string(stgdict->format, "}");
+		PyMem_Free(ptr);
 		if (stgdict->format == NULL)
 			return -1;
 	}

Modules/_fileio.c

@@ -278,6 +278,7 @@ fileio_init(PyObject *oself, PyObject *args, PyObject *kwds)
 	ret = -1;
 
  done:
+	PyMem_Free(name);
 	return ret;
 }
 

Modules/signalmodule.c

@@ -784,7 +784,8 @@ initsignal(void)
 #if defined (HAVE_SETITIMER) || defined (HAVE_GETITIMER)
     ItimerError = PyErr_NewException("signal.ItimerError", 
          PyExc_IOError, NULL);
-    PyDict_SetItemString(d, "ItimerError", ItimerError);
+    if (ItimerError != NULL)
+    	PyDict_SetItemString(d, "ItimerError", ItimerError);
 #endif
 
         if (!PyErr_Occurred())

Objects/stringlib/formatter.h

@@ -641,7 +641,10 @@ format_int_or_long_internal(PyObject *value, const InternalFormatSpec *format,
 	    /* We know this can't fail, since we've already
 	       reserved enough space. */
 	    STRINGLIB_CHAR *pstart = p + n_leading_chars;
-	    int r = STRINGLIB_GROUPING(pstart, n_digits, n_digits,
+#ifndef NDEBUG
+	    int r =
+#endif
+		STRINGLIB_GROUPING(pstart, n_digits, n_digits,
 			   spec.n_total+n_grouping_chars-n_leading_chars,
 			   NULL, 0);
 	    assert(r);

Objects/structseq.c

@@ -32,6 +32,8 @@ PyStructSequence_New(PyTypeObject *type)
 	PyStructSequence *obj;
 
 	obj = PyObject_New(PyStructSequence, type);
+	if (obj == NULL)
+		return NULL;
 	Py_SIZE(obj) = VISIBLE_SIZE_TP(type);
 
 	return (PyObject*) obj;
@@ -522,10 +524,16 @@ PyStructSequence_InitType(PyTypeObject *type, PyStructSequence_Desc *desc)
 	Py_INCREF(type);
 
 	dict = type->tp_dict;
-	PyDict_SetItemString(dict, visible_length_key, 
-		       PyInt_FromLong((long) desc->n_in_sequence));
-	PyDict_SetItemString(dict, real_length_key, 
-		       PyInt_FromLong((long) n_members));
-	PyDict_SetItemString(dict, unnamed_fields_key, 
-		       PyInt_FromLong((long) n_unnamed_members));
+#define SET_DICT_FROM_INT(key, value)				\
+	do {							\
+		PyObject *v = PyInt_FromLong((long) value);	\
+		if (v != NULL) {				\
+			PyDict_SetItemString(dict, key, v);	\
+			Py_DECREF(v);				\
+		}						\
+	} while (0)
+
+	SET_DICT_FROM_INT(visible_length_key, desc->n_in_sequence);
+	SET_DICT_FROM_INT(real_length_key, n_members);
+	SET_DICT_FROM_INT(unnamed_fields_key, n_unnamed_members);
 }

Python/getargs.c

@@ -1312,7 +1312,7 @@ convertbuffer(PyObject *arg, void **p, char **errmsg)
 }
 
 static int
-getbuffer(PyObject *arg, Py_buffer *view, char**errmsg)
+getbuffer(PyObject *arg, Py_buffer *view, char **errmsg)
 {
 	void *buf;
 	Py_ssize_t count;
@@ -1322,8 +1322,10 @@ getbuffer(PyObject *arg, Py_buffer *view, char**errmsg)
 		return -1;
 	}
 	if (pb->bf_getbuffer) {
-		if (pb->bf_getbuffer(arg, view, 0) < 0)
+		if (pb->bf_getbuffer(arg, view, 0) < 0) {
+			*errmsg = "convertible to a buffer";
 			return -1;
+		}
 		if (!PyBuffer_IsContiguous(view, 'C')) {
 			*errmsg = "contiguous buffer";
 			return -1;
@@ -1332,8 +1334,10 @@ getbuffer(PyObject *arg, Py_buffer *view, char**errmsg)
 	}
 
 	count = convertbuffer(arg, &buf, errmsg);
-	if (count < 0)
+	if (count < 0) {
+		*errmsg = "convertible to a buffer";
 		return count;
+	}
 	PyBuffer_FillInfo(view, NULL, buf, count, 1, 0);
 	return 0;
 }

Python/pythonrun.c

@@ -132,8 +132,8 @@ Py_InitializeEx(int install_sigs)
 	PyThreadState *tstate;
 	PyObject *bimod, *sysmod;
 	char *p;
-	char *icodeset; /* On Windows, input codeset may theoretically 
-			   differ from output codeset. */
+	char *icodeset = NULL; /* On Windows, input codeset may theoretically 
+			          differ from output codeset. */
 	char *codeset = NULL;
 	char *errors = NULL;
 	int free_codeset = 0;