Ensure that compiler_exit_scope() is called as necessary to free memory

allocated by compiler_enter_scope().  Change return type for
compiler_exit_scope() to be void.

diff --git a/Python/compile.c b/Python/compile.c
index 8426038221b05d89addefec4c23ebe822cde8e87..5195f5651f1e3a606a13bcf09f19a2f4f5801e76 100644 (file)
--- a/Python/compile.c
+++ b/Python/compile.c
@@ -1113,7 +1113,7 @@ compiler_enter_scope(struct compiler *c, identifier name, void *key,
        return 1;
 }
 
-static int
+static void
 compiler_exit_scope(struct compiler *c)
 {
        int n;
@@ -1126,14 +1126,14 @@ compiler_exit_scope(struct compiler *c)
        if (n >= 0) {
                wrapper = PyList_GET_ITEM(c->c_stack, n);
                c->u = (struct compiler_unit *)PyCObject_AsVoidPtr(wrapper);
+               /* we are deleting from a list so this really shouldn't fail */
                if (PySequence_DelItem(c->c_stack, n) < 0)
-                       return 0;
+                       Py_FatalError("compiler_exit_scope()");
                compiler_unit_check(c->u);
        }
        else
                c->u = NULL;
 
-       return 1; /* XXX void? */
 }
 
 /* Allocate a new block and return a pointer to it.
@@ -1701,8 +1701,10 @@ compiler_mod(struct compiler *c, mod_ty mod)
                return NULL;
        switch (mod->kind) {
        case Module_kind: 
-               if (!compiler_body(c, mod->v.Module.body))
+               if (!compiler_body(c, mod->v.Module.body)) {
+                       compiler_exit_scope(c);
                        return 0;
+               }
                break;
        case Interactive_kind:
                c->c_interactive = 1;
@@ -1872,8 +1874,10 @@ compiler_function(struct compiler *c, stmt_ty s)
         docstring = compiler_isdocstring(st);
         if (docstring)
             first_const = st->v.Expr.value->v.Str.s;
-        if (compiler_add_o(c, c->u->u_consts, first_const) < 0)
+        if (compiler_add_o(c, c->u->u_consts, first_const) < 0)  {
+           compiler_exit_scope(c);
             return 0;
+       }
 
         /* unpack nested arguments */
        compiler_arguments(c, args);
@@ -1889,9 +1893,9 @@ compiler_function(struct compiler *c, stmt_ty s)
                VISIT(c, stmt, s2);
        }
        co = assemble(c, 1);
+       compiler_exit_scope(c);
        if (co == NULL)
                return 0;
-       compiler_exit_scope(c);
 
         compiler_make_closure(c, co, asdl_seq_LEN(args->defaults));
 
@@ -1923,6 +1927,7 @@ compiler_class(struct compiler *c, stmt_ty s)
         str = PyString_InternFromString("__name__");
        if (!str || !compiler_nameop(c, str, Load)) {
                Py_XDECREF(str);
+               compiler_exit_scope(c);
                return 0;
         }
         
@@ -1930,19 +1935,22 @@ compiler_class(struct compiler *c, stmt_ty s)
         str = PyString_InternFromString("__module__");
        if (!str || !compiler_nameop(c, str, Store)) {
                Py_XDECREF(str);
+               compiler_exit_scope(c);
                return 0;
         }
         Py_DECREF(str);
 
-       if (!compiler_body(c, s->v.ClassDef.body))
+       if (!compiler_body(c, s->v.ClassDef.body)) {
+               compiler_exit_scope(c);
                return 0;
+       }
 
        ADDOP(c, LOAD_LOCALS);
        ADDOP(c, RETURN_VALUE);
        co = assemble(c, 1);
+       compiler_exit_scope(c);
        if (co == NULL)
                return 0;
-       compiler_exit_scope(c);
 
         compiler_make_closure(c, co, 0);
        ADDOP_I(c, CALL_FUNCTION, 0);
@@ -1976,9 +1984,9 @@ compiler_lambda(struct compiler *c, expr_ty e)
        VISIT(c, expr, e->v.Lambda.body);
        ADDOP(c, RETURN_VALUE);
        co = assemble(c, 1);
+       compiler_exit_scope(c);
        if (co == NULL)
                return 0;
-       compiler_exit_scope(c);
 
         compiler_make_closure(c, co, asdl_seq_LEN(args->defaults));
        Py_DECREF(name);
@@ -3149,9 +3157,9 @@ compiler_genexp(struct compiler *c, expr_ty e)
        compiler_genexp_generator(c, e->v.GeneratorExp.generators, 0,
                                  e->v.GeneratorExp.elt);
        co = assemble(c, 1);
+       compiler_exit_scope(c);
        if (co == NULL)
                return 0;
-       compiler_exit_scope(c);
 
         compiler_make_closure(c, co, 0);
        VISIT(c, expr, outermost_iter);