diff --git a/Python/bltinmodule.c b/Python/bltinmodule.c
index 3def080..a07b78c 100644
--- a/Python/bltinmodule.c
+++ b/Python/bltinmodule.c
@@ -313,7 +313,7 @@
             ok = PyObject_IsTrue(good);
             Py_DECREF(good);
         }
-        if (ok) {
+        if (ok > 0) {
             if (j < len)
                 PyList_SET_ITEM(result, j, item);
             else {
@@ -324,8 +324,11 @@
             }
             ++j;
         }
-        else
+        else {
             Py_DECREF(item);
+            if (ok < 0)
+                goto Fail_result_it;
+        }
     }
 
 
@@ -2784,12 +2787,15 @@
         }
         ok = PyObject_IsTrue(good);
         Py_DECREF(good);
-        if (ok) {
+        if (ok > 0) {
             if (PyTuple_SetItem(result, j++, item) < 0)
                 goto Fail_1;
         }
-        else
+        else {
             Py_DECREF(item);
+            if (ok < 0)
+                goto Fail_1;
+        }
     }
 
     if (_PyTuple_Resize(&result, j) < 0)
@@ -2851,7 +2857,7 @@
             ok = PyObject_IsTrue(good);
             Py_DECREF(good);
         }
-        if (ok) {
+        if (ok > 0) {
             Py_ssize_t reslen;
             if (!PyString_Check(item)) {
                 PyErr_SetString(PyExc_TypeError, "can't filter str to str:"
@@ -2917,6 +2923,8 @@
                     }
         }
         Py_DECREF(item);
+        if (ok < 0)
+            goto Fail_1;
     }
 
     if (j < outlen)
@@ -2977,7 +2985,7 @@
             ok = PyObject_IsTrue(good);
             Py_DECREF(good);
         }
-        if (ok) {
+        if (ok > 0) {
             Py_ssize_t reslen;
             if (!PyUnicode_Check(item)) {
                 PyErr_SetString(PyExc_TypeError,
@@ -3032,6 +3040,8 @@
                     }
         }
         Py_DECREF(item);
+        if (ok < 0)
+            goto Fail_1;
     }
 
     if (j < outlen)
diff --git a/Python/import.c b/Python/import.c
index e95b7c0..53c9b29 100644
--- a/Python/import.c
+++ b/Python/import.c
@@ -1043,7 +1043,10 @@
                 name, pathname);
         if (cpathname) {
             PyObject *ro = PySys_GetObject("dont_write_bytecode");
-            if (ro == NULL || !PyObject_IsTrue(ro))
+            int b = (ro == NULL) ? 0 : PyObject_IsTrue(ro);
+            if (b < 0)
+                goto error_exit;
+            if (!b)
                 write_compiled_module(co, cpathname, &st);
         }
     }
@@ -2200,7 +2203,13 @@
     }
 
     if (fromlist != NULL) {
-        if (fromlist == Py_None || !PyObject_IsTrue(fromlist))
+        int b = (fromlist == Py_None) ? 0 : PyObject_IsTrue(fromlist);
+        if (b < 0) {
+            Py_DECREF(tail);
+            Py_DECREF(head);
+            goto error_exit;
+        }
+        if (!b)
             fromlist = NULL;
     }