diff --git a/Misc/NEWS b/Misc/NEWS
index 85587eb..7a8e4de 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -49,6 +49,7 @@
 
 - Fix itertools.count(n) to work with negative numbers again.
 
+- Make regex engine raise MemoryError if allocating memory fails.
 
 Library
 -------
diff --git a/Modules/_sre.c b/Modules/_sre.c
index 9e3a1e8..c1eb71c 100644
--- a/Modules/_sre.c
+++ b/Modules/_sre.c
@@ -1166,9 +1166,10 @@
 
             /* install new repeat context */
             ctx->u.rep = (SRE_REPEAT*) PyObject_MALLOC(sizeof(*ctx->u.rep));
-            /* XXX(nnorwitz): anything else we need to do on error? */
-            if (!ctx->u.rep)
+            if (!ctx->u.rep) {
+                PyErr_NoMemory();
                 RETURN_FAILURE;
+            }
             ctx->u.rep->count = -1;
             ctx->u.rep->pattern = ctx->pattern;
             ctx->u.rep->prev = state->repeat;
@@ -1884,6 +1885,8 @@
     }
 
     TRACE(("|%p|%p|END\n", PatternObject_GetCode(self), state.ptr));
+    if (PyErr_Occurred())
+        return NULL;
 
     state_fini(&state);
 
@@ -1922,6 +1925,9 @@
 
     state_fini(&state);
 
+    if (PyErr_Occurred())
+        return NULL;
+
     return pattern_new_match(self, &state, status);
 }
 
@@ -2071,6 +2077,9 @@
 #endif
         }
 
+	if (PyErr_Occurred())
+	    goto error;
+
         if (status <= 0) {
             if (status == 0)
                 break;
@@ -2198,6 +2207,9 @@
 #endif
         }
 
+	if (PyErr_Occurred())
+	    goto error;
+
         if (status <= 0) {
             if (status == 0)
                 break;
@@ -2347,6 +2359,9 @@
 #endif
         }
 
+	if (PyErr_Occurred())
+	    goto error;
+
         if (status <= 0) {
             if (status == 0)
                 break;
@@ -3250,6 +3265,8 @@
         status = sre_umatch(state, PatternObject_GetCode(self->pattern));
 #endif
     }
+    if (PyErr_Occurred())
+        return NULL;
 
     match = pattern_new_match((PatternObject*) self->pattern,
                                state, status);
@@ -3281,6 +3298,8 @@
         status = sre_usearch(state, PatternObject_GetCode(self->pattern));
 #endif
     }
+    if (PyErr_Occurred())
+        return NULL;
 
     match = pattern_new_match((PatternObject*) self->pattern,
                                state, status);