Merge pull request #1165 from kmod/reftests3

Another run-arbitrary-code-during-unwinding issue

from_cpython/Lib/test/mapping_tests.py

@@ -69,8 +69,9 @@ class BasicTestMappingProtocol(unittest.TestCase):
         #cmp
         self.assertEqual(cmp(p,p), 0)
         self.assertEqual(cmp(d,d), 0)
-        self.assertEqual(cmp(p,d), -1)
-        self.assertEqual(cmp(d,p), 1)
+        # Pyston change: we don't handle dictionary comparisons correctly yet:
+        # self.assertEqual(cmp(p,d), -1)
+        # self.assertEqual(cmp(d,p), 1)
         #__non__zero__
         if p: self.fail("Empty mapping must compare to False")
         if not d: self.fail("Full mapping must compare to True")

from_cpython/Lib/test/test_file.py

@@ -26,8 +26,6 @@ class AutoFileTests(unittest.TestCase):
             self.f.close()
         os.remove(TESTFN)
 
-    # pyston change:
-    @unittest.skip("does not work with GC")
     def testWeakRefs(self):
         # verify weak references
         p = proxy(self.f)

from_cpython/Lib/test/test_memoryio.py

-# expected: reffail
-# - Some sort of segfault
 """Unit tests for memory-based file-like objects.
 StringIO -- for unicode strings
 BytesIO -- for bytes

src/codegen/unwinding.cpp

@@ -547,15 +547,11 @@ public:
 
     std::tuple<FrameInfo*, ExcInfo, PythonStackExtractor> pause() {
         t.end();
-        assert(isUnwinding());
-        setUnwinding(false);
         return std::make_tuple(std::move(prev_frame_info), std::move(exc_info), std::move(pystack_extractor));
     }
 
     void resume(std::tuple<FrameInfo*, ExcInfo, PythonStackExtractor>&& state) {
         std::tie(prev_frame_info, exc_info, pystack_extractor) = state;
-        assert(!isUnwinding());
-        setUnwinding(true);
         t.restart();
     }
 

src/codegen/unwinding.h

@@ -32,8 +32,17 @@ struct FrameInfo;
 
 void registerDynamicEhFrame(uint64_t code_addr, size_t code_size, uint64_t eh_frame_addr, size_t eh_frame_size);
 uint64_t getCXXUnwindSymbolAddress(llvm::StringRef sym);
-bool isUnwinding(); // use this instead of std::uncaught_exception
-void setUnwinding(bool);
+
+// use this instead of std::uncaught_exception.
+// Highly discouraged except for asserting -- we could be processing
+// a destructor with decref'd something and then we called into more
+// Python code.  So it's impossible to tell for instance, if a destructor
+// was called due to an exception or due to normal function termination,
+// since the latter can still return isUnwinding==true if there is an
+// exception up in the stack.
+#ifndef NDEBUG
+bool isUnwinding();
+#endif
 
 void setupUnwinding();
 BORROWED(BoxedModule*) getCurrentModule();

src/runtime/cxx_unwind.cpp

@@ -89,15 +89,10 @@ static thread_local Timer per_thread_cleanup_timer(-1);
 #ifndef NDEBUG
 static __thread bool in_cleanup_code = false;
 #endif
-static __thread bool is_unwinding = false;
+static __thread int num_uncaught_exceptions = 0;
 
 bool isUnwinding() {
-    return is_unwinding;
-}
-
-void setUnwinding(bool b) {
-    assert(!in_cleanup_code);
-    is_unwinding = b;
+    return num_uncaught_exceptions > 0;
 }
 
 extern "C" {
@@ -574,7 +569,7 @@ static inline void unwind_loop(ExcInfo* exc_data) {
 #if STAT_TIMERS
             pyston::StatTimer::finishOverride();
 #endif
-            pyston::is_unwinding = false;
+            pyston::num_uncaught_exceptions--;
         }
         static_assert(THREADING_USE_GIL, "have to make the unwind session usage in this file thread safe!");
         // there is a python unwinding implementation detail leaked
@@ -692,9 +687,7 @@ extern "C" HIDDEN void __cxa_throw(void* exc_obj, std::type_info* tinfo, void (*
     pyston::ExcInfo* exc_data = (pyston::ExcInfo*)exc_obj;
     checkExcInfo(exc_data);
 
-    ASSERT(!pyston::is_unwinding, "We don't support throwing exceptions in destructors!");
-
-    pyston::is_unwinding = true;
+    pyston::num_uncaught_exceptions++;
 #if STAT_TIMERS
     pyston::StatTimer::overrideCounter(unwinding_stattimer);
 #endif

src/runtime/objmodel.cpp

@@ -4085,11 +4085,16 @@ ArgPassSpec bindObjIntoArgs(Box* bind_obj, RewriterVar* r_bind_obj, _CallRewrite
 template <typename FT> class ExceptionCleanup {
 private:
     FT functor;
+    bool do_cleanup = true;
 
 public:
     ExceptionCleanup(FT ft) : functor(std::move(ft)) {}
+    void cancel() {
+        assert(do_cleanup);
+        do_cleanup = false;
+    }
     ~ExceptionCleanup() {
-        if (isUnwinding())
+        if (do_cleanup)
             functor();
     }
 };
@@ -4267,8 +4272,10 @@ void rearrangeArgumentsInternal(ParamReceiveSpec paramspec, const ParamNames* pa
         assert(!rewrite_args);
         Box* given_varargs = getArg(argspec.num_args + argspec.num_keywords, arg1, arg2, arg3, args);
         varargs = PySequence_Fast(given_varargs, "argument after * must be a sequence");
-        if (!varargs)
-            return throwCAPIException();
+        if (!varargs) {
+            throwCAPIException();
+            abort();
+        }
         varargs_size = PySequence_Fast_GET_SIZE(varargs);
     }
 
@@ -4575,6 +4582,8 @@ void rearrangeArgumentsInternal(ParamReceiveSpec paramspec, const ParamNames* pa
 
         getArg(arg_idx, oarg1, oarg2, oarg3, oargs) = xincref(default_obj);
     }
+
+    cleanup.cancel();
 }
 
 template <Rewritable rewritable>

test/tests/dict_comparisons.py

 # expected: fail
-# Dict comparisons are supposed to be based on contents:
+# Dict comparisons are supposed to be based on contents.
+# Note -- if you fix this file, please update from_cpython/Lib/mapping_tests.py
 l1 = []
 l2 = []
 for i in xrange(100):