[antlr-interest] Bug in ANTLR C runtime - Incorrect getCharPositionInLine on first line

[Ales Teska]

Hi,

I'm using ANTLR3 in one of my project and it seems that I found small  
bug in ANTLR C (version 3.2, 3.1.3 is also corrupted).
I do not know if this is correct way of reporting bugs but ...

ANTLR3 C runtime returns incorrect values of CharPositionInLine for  
tokens on first line of input. This is eventually propagated to tokens.
I wrote small program to demonstrate this behavior - it is available  
here: http://devel-www.cyber.cz/files/tmp/antlrc3-bug-pack.zip

Bug causes token stream post-processing a little bit more complicated  
than it can ideally be ...

Here is expected output (produced by Python target).
First character is from input.txt, second is result of  
getCharPositionInLine():

--- cut --- cut --- cut ---
1 0
2 2
3 4
\n 5
1 0
2 2
3 4
\n 5
--- cut --- cut --- cut ---

and here is actual output from C target:

--- cut --- cut --- cut ---
1 4294967295
2 1
3 3
\n 4
1 0
2 2
3 4
\n 5
--- cut --- cut --- cut ---

Please notice that first token has undefined value in  
getCharPositionInLine() and rest till end of line is shifted by -1.

Workaround is to set ctx->pLexer->input->charPositionInLine to zero  
after constructing lexer and before actual lexing/parsing.

Regards,
Ales Teska

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