Centaur's error?

[jbenz@cnam.cnam.fr (Judith Benzakki)]

Dear User,
We are using Centaur for describing Vhdl's grammar (approching
ADA's grammar). We have described the METAL and the PPML and have
some problems on parsing Vhdl's files.
No errors on the type checker METAL.
No errors on compilation of the METAL
But when we read a Vhdl's file, the tree obtained is wrong and the
Centaur's error is :
"INTERNAL ERROR : STACK empty you are at WITT'S END
Imcompatibility between CENTAUR tables and PARSER'S tables."

We have worked on this error for a week and now can not go on.
Thank's for answers.
Judith.
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Judith Benzakki                          Phone:+33-1- 60 77 97 40
IIE-CNAM                                 Fax : +33-1-60 77 96 99
18, Allee Jean Rostand                   email: jbenz@cnam.cnam.fr
91002 evry cedex
France
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