Fix volatile vs. pointer confusion

Variables used after a longjmp() need to be declared volatile.  In
case of a pointer, it's the pointer itself that needs to be declared
volatile, not the pointed-to value.  So we need

    PyObject *volatile items;

instead of

    volatile PyObject *items;  /* wrong */

Discussion: https://www.postgresql.org/message-id/flat/f747368d-9e1a-c46a-ac76-3c27da32e8e4%402ndquadrant.com

diff --git a/contrib/hstore_plpython/hstore_plpython.c b/contrib/hstore_plpython/hstore_plpython.c
index b184324ebf0d90c058ff0376bcfd1e066b8e2f4b..25328322364350f60019b06118ceffb0a216fae3 100644 (file)
--- a/contrib/hstore_plpython/hstore_plpython.c
+++ b/contrib/hstore_plpython/hstore_plpython.c
@@ -124,7 +124,7 @@ Datum
 plpython_to_hstore(PG_FUNCTION_ARGS)
 {
    PyObject   *dict;
-   volatile PyObject *items_v = NULL;
+   PyObject *volatile items = NULL;
    int32       pcount;
    HStore     *out;
 
@@ -135,14 +135,13 @@ plpython_to_hstore(PG_FUNCTION_ARGS)
                 errmsg("not a Python mapping")));
 
    pcount = PyMapping_Size(dict);
-   items_v = PyMapping_Items(dict);
+   items = PyMapping_Items(dict);
 
    PG_TRY();
    {
        int32       buflen;
        int32       i;
        Pairs      *pairs;
-       PyObject   *items = (PyObject *) items_v;
 
        pairs = palloc(pcount * sizeof(*pairs));
 
@@ -173,14 +172,14 @@ plpython_to_hstore(PG_FUNCTION_ARGS)
                pairs[i].isnull = false;
            }
        }
-       Py_DECREF(items_v);
+       Py_DECREF(items);
 
        pcount = hstoreUniquePairs(pairs, pcount, &buflen);
        out = hstorePairs(pairs, pcount, buflen);
    }
    PG_CATCH();
    {
-       Py_DECREF(items_v);
+       Py_DECREF(items);
        PG_RE_THROW();
    }
    PG_END_TRY();