Fix parser so that it guarantees the precondition S = G = NULL and postcondition...

G = NULL on error. We need to clean the stack in all cases to prevent a small memory leak. Note that if S starts as NULL and is non-NULL at the end, then in G is non-NULL.

diff --git a/lib/cgraph/grammar.y b/lib/cgraph/grammar.y
index b43f493a95d9b12d01a353bd8dd0b97162606ca1..2f3f807bbc600bd32d0cbd45c0fc69f741e0e323 100644 (file)
--- a/lib/cgraph/grammar.y
+++ b/lib/cgraph/grammar.y
@@ -95,8 +95,8 @@ static gstack_t *S;
 
 %%
 
-graph          :  hdr body {endgraph();}
-                       |  error        {freestack(); if (G) {endgraph(); agclose(G); G = Ag_G_global = NIL(Agraph_t*);}}
+graph          :  hdr body {freestack(); endgraph();}
+                       |  error        {if (G) {freestack(); endgraph(); agclose(G); G = Ag_G_global = NIL(Agraph_t*);}}
                        |  /* empty */
                        ;