Years in the making.
objimpl.h, pymem.h: Stop mapping PyMem_{Del, DEL} and PyMem_{Free, FREE}
to PyObject_{Free, FREE} in a release build. They're aliases for the
system free() now.
_subprocess.c/sp_handle_dealloc(): Since the memory was originally
obtained via PyObject_NEW, it must be released via PyObject_FREE (or
_DEL).
pythonrun.c, tokenizer.c, parsermodule.c: I lost count of the number of
PyObject vs PyMem mismatches in these -- it's like the specific
function called at each site was picked at random, sometimes even with
memory obtained via PyMem getting released via PyObject. Changed most
to use PyObject uniformly, since the blobs allocated are predictably
small in most cases, and obmalloc is generally faster than system
mallocs then.
If extension modules in real life prove as sloppy as Python's front
end, we'll have to revert the objimpl.h + pymem.h part of this patch.
Note that no problems will show up in a debug build (all calls still go
thru obmalloc then). Problems will show up only in a release build, most
likely segfaults.
diff --git a/Include/objimpl.h b/Include/objimpl.h
index 7c68194..447a56e 100644
--- a/Include/objimpl.h
+++ b/Include/objimpl.h
@@ -101,7 +101,7 @@
/* Macros */
#ifdef WITH_PYMALLOC
-#ifdef PYMALLOC_DEBUG
+#ifdef PYMALLOC_DEBUG /* WITH_PYMALLOC && PYMALLOC_DEBUG */
PyAPI_FUNC(void *) _PyObject_DebugMalloc(size_t nbytes);
PyAPI_FUNC(void *) _PyObject_DebugRealloc(void *p, size_t nbytes);
PyAPI_FUNC(void) _PyObject_DebugFree(void *p);
@@ -124,11 +124,7 @@
#else /* ! WITH_PYMALLOC */
#define PyObject_MALLOC PyMem_MALLOC
#define PyObject_REALLOC PyMem_REALLOC
-/* This is an odd one! For backward compatibility with old extensions, the
- PyMem "release memory" functions have to invoke the object allocator's
- free() function. When pymalloc isn't enabled, that leaves us using
- the platform free(). */
-#define PyObject_FREE free
+#define PyObject_FREE PyMem_FREE
#endif /* WITH_PYMALLOC */
diff --git a/Include/pymem.h b/Include/pymem.h
index f8aef29..671f967 100644
--- a/Include/pymem.h
+++ b/Include/pymem.h
@@ -59,6 +59,7 @@
/* Redirect all memory operations to Python's debugging allocator. */
#define PyMem_MALLOC PyObject_MALLOC
#define PyMem_REALLOC PyObject_REALLOC
+#define PyMem_FREE PyObject_FREE
#else /* ! PYMALLOC_DEBUG */
@@ -68,14 +69,10 @@
pymalloc. To solve these problems, allocate an extra byte. */
#define PyMem_MALLOC(n) malloc((n) ? (n) : 1)
#define PyMem_REALLOC(p, n) realloc((p), (n) ? (n) : 1)
+#define PyMem_FREE free
#endif /* PYMALLOC_DEBUG */
-/* In order to avoid breaking old code mixing PyObject_{New, NEW} with
- PyMem_{Del, DEL} and PyMem_{Free, FREE}, the PyMem "release memory"
- functions have to be redirected to the object deallocator. */
-#define PyMem_FREE PyObject_FREE
-
/*
* Type-oriented memory interface
* ==============================
@@ -95,11 +92,11 @@
#define PyMem_RESIZE(p, type, n) \
( (p) = (type *) PyMem_REALLOC((p), (n) * sizeof(type)) )
-/* In order to avoid breaking old code mixing PyObject_{New, NEW} with
- PyMem_{Del, DEL} and PyMem_{Free, FREE}, the PyMem "release memory"
- functions have to be redirected to the object deallocator. */
-#define PyMem_Del PyObject_Free
-#define PyMem_DEL PyObject_FREE
+/* PyMem{Del,DEL} are left over from ancient days, and shouldn't be used
+ * anymore. They're just confusing aliases for PyMem_{Free,FREE} now.
+ */
+#define PyMem_Del PyMem_Free
+#define PyMem_DEL PyMem_FREE
#ifdef __cplusplus
}