* TODO: Remove dead items.

[bison.git] / data / glr.c

diff --git a/data/glr.c b/data/glr.c
index 13fd2ff2872c4914aaa9aecd97ad67841fdf47e8..e67573b6db9d5f41c09312d7d0e8a24ecf3fc2b4 100644 (file)
--- a/data/glr.c
+++ b/data/glr.c
@@ -1803,6 +1803,57 @@ yyreportAmbiguity (yySemanticOption* yyx0,
   return yyabort;
 }
 
+/** Starting at and including state S1, resolve the location for each of the
+ *  previous N1 states that is unresolved.  The first semantic option of a state
+ *  is always chosen.  */
+static void
+yyresolveLocations (yyGLRState* yys1, int yyn1,
+                   yyGLRStack *yystackp]b4_user_formals[)
+{
+  if (0 < yyn1)
+    {
+      yyresolveLocations (yys1->yypred, yyn1 - 1, yystackp]b4_user_args[);
+      if (!yys1->yyresolved)
+       {
+         yySemanticOption *yyoption;
+         yyGLRStackItem yyrhsloc[1 + YYMAXRHS];
+         int yynrhs;
+         int yychar_current;
+         YYSTYPE yylval_current;
+         YYLTYPE yylloc_current;
+         yyoption = yys1->yysemantics.yyfirstVal;
+         YYASSERT (yyoption != NULL);
+         yynrhs = yyrhsLength (yyoption->yyrule);
+         if (yynrhs > 0)
+           {
+             yyGLRState *yys;
+             int yyn;
+             yyresolveLocations (yyoption->yystate, yynrhs,
+                                 yystackp]b4_user_args[);
+             for (yys = yyoption->yystate, yyn = yynrhs;
+                  yyn > 0;
+                  yys = yys->yypred, yyn -= 1)
+               yyrhsloc[yyn].yystate.yyloc = yys->yyloc;
+           }
+         else
+           {
+             yyGLRState *yyprevious = yyoption->yystate;
+             YYASSERT (yyprevious->yyresolved);
+             yyrhsloc[0].yystate.yyloc = yyprevious->yyloc;
+           }
+         yychar_current = yychar;
+         yylval_current = yylval;
+         yylloc_current = yylloc;
+         yychar = yyoption->yyrawchar;
+         yylval = yyoption->yyval;
+         yylloc = yyoption->yyloc;
+         YYLLOC_DEFAULT ((yys1->yyloc), yyrhsloc, yynrhs);
+         yychar = yychar_current;
+         yylval = yylval_current;
+         yylloc = yylloc_current;
+       }
+    }
+}
 
 /** Resolve the ambiguity represented in state S, perform the indicated
  *  actions, and set the semantic value of S.  If result != yyok, the chain of
@@ -1837,6 +1888,7 @@ yyresolveValue (yyGLRState* yys, yyGLRStack* yystackp]b4_user_formals[)
          switch (yypreference (yybest, yyp))
            {
            case 0:
+             yyresolveLocations (yys, 1, yystackp]b4_user_args[);
              return yyreportAmbiguity (yybest, yyp]b4_pure_args[);
              break;
            case 1: