ANTLR : no start rule (no rule can obviously be followed by EOF)

The problem is that Antlr identifies "start" rules (ones that can end with EOF) by looking for rules that are not used anywhere else in the grammar.

Then, you cannot call your "start" rule inside another rule. Otherwise your "start"' rule is not considered as the real "start" rule.

Source : http://thesoftwarelife.blogspot.fr/2008/07/antlr-frustrations.html