Index: Modules/_lsprof.c
===================================================================
--- Modules/_lsprof.c	(revision 55841)
+++ Modules/_lsprof.c	(working copy)
@@ -369,11 +369,20 @@
 	ProfilerEntry *profEntry;
 	ProfilerContext *pContext;
 
+        /* In the case of entering a generator expression frame via a
+         * throw (gen_send_ex(.., 1)), we may already have an
+         * Exception set here. We must not mess around with this
+         * exception, and some of the code under here assumes that
+         * PyErr_* is its own to mess around with, so we have to
+         * save and restore any current exception. */
+        PyObject *last_type, *last_value, *last_tb;
+        PyErr_Fetch(&last_type, &last_value, &last_tb);
+
 	profEntry = getEntry(pObj, key);
 	if (profEntry == NULL) {
 		profEntry = newProfilerEntry(pObj, key, userObj);
 		if (profEntry == NULL)
-			return;
+			goto restorePyerr;
 	}
 	/* grab a ProfilerContext out of the free list */
 	pContext = pObj->freelistProfilerContext;
@@ -386,10 +396,13 @@
 			malloc(sizeof(ProfilerContext));
 		if (pContext == NULL) {
 			pObj->flags |= POF_NOMEMORY;
-			return;
+			goto restorePyerr;
 		}
 	}
 	initContext(pObj, pContext, profEntry);
+	
+restorePyerr:
+	PyErr_Restore(last_type, last_value, last_tb);
 }
 
 static void