Stackless issue python#154: fix STACKLESS_PROMOTE_WRAPPER/METHOD

Fix the macros STACKLESS_PROMOTE_WRAPPER and STACKLESS_PROMOTE_METHOD to use
"&&" instead of "&" for logical values. By chance the bug was harmless.

(cherry picked from commit b940f65)

Author: akruis

Stackless/changelog.txt

@@ -9,6 +9,9 @@ What's New in Stackless 3.X.X?
 
 *Release date: 20XX-XX-XX*
 
+- https://github.com/stackless-dev/stackless/issues/154
+  Fix a minor bug in STACKLESS_PROMOTE_WRAPPER and STACKLESS_PROMOTE_METHOD.
+
 - https://github.com/stackless-dev/stackless/issues/150
   The prototype of PyStackless_GetCurrentId(void) was missing from
   stackless_api.h. It is now defined.

Stackless/core/stackless_impl.h

@@ -474,11 +474,11 @@ PyTaskletObject * slp_get_watchdog(PyThreadState *ts, int interrupt);
 #define STACKLESS_PROMOTE_METHOD(obj, meth) do { \
     if ((Py_TYPE(obj)->tp_flags & Py_TPFLAGS_HAVE_STACKLESS_EXTENSION) && \
      Py_TYPE(obj)->tp_as_mapping) \
-        slp_try_stackless = stackless & Py_TYPE(obj)->tp_as_mapping->slpflags.meth; \
+        slp_try_stackless = stackless && Py_TYPE(obj)->tp_as_mapping->slpflags.meth; \
 } while (0)
 
 #define STACKLESS_PROMOTE_WRAPPER(wp) \
-    (slp_try_stackless = stackless & wp->descr->d_slpmask)
+    (slp_try_stackless = stackless && wp->descr->d_slpmask)
 
 #define STACKLESS_PROMOTE_ALL() ((void)(slp_try_stackless = stackless, NULL))