[antlr-interest] Problem with AST type in tree grammar in C target

[Kevin J. Cummings]

I'm trying to implement a Tree Grammar for my Lexer and Parser.

In my Tree Grammar, I specify:

> tree grammar m2Emit;
> 
> options { language=C;
>           ASTLabelType=pANTLR3_COMMON_TREE;
>         }

Further down, I have a rule:

> stmt
>     : ^(ASSIGN assLhs=ref assExp=exp )
>     ;

When I compile, I see the following errors:

> m2Emit.c: In function ‘m2Emit_exp_return exp(m2Emit_Ctx_struct*)’:
> m2Emit.c:1113:20: error: cannot convert ‘ANTLR3_BASE_TREE_struct*’ to ‘ANTLR3_COMMON_TREE_struct*’ in assignment
> m2Emit.c: In function ‘m2Emit_ref_return ref(m2Emit_Ctx_struct*)’:
> m2Emit.c:2193:20: error: cannot convert ‘ANTLR3_BASE_TREE_struct*’ to ‘ANTLR3_COMMON_TREE_struct*’ in assignment

In m2Emit.c, I can see the following code:

>     retval.start = LT(1); retval.stop = retval.start;

It looks like LT(1) is an ANTLR3_BASE_TREE_struct*, while retval.start
is an ANTLR3_COMMON_TREE_struct*.

Is this a bug, or did I miss some important documentation?

In case it matters, I'm trying to compile as C++....


-- 
Kevin J. Cummings
kjchome at verizon.net
cummings at kjchome.homeip.net
cummings at kjc386.framingham.ma.us
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