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Re: Character error not reported

From: Akim Demaille
Subject: Re: Character error not reported
Date: Tue, 18 Jun 2019 11:26:49 +0200

[Resent, thanks Uxio]

Hi Hans,

> Le 17 juin 2019 à 15:12, Hans Åberg <address@hidden> a écrit :
> When a byte with high bit set that is not used in the grammar, the parser 
> generated by Bison 3.4.1, does not report an error, only if the high bit is 
> not set.

This is hard to believe.  I suspect your problem is elsewhere.

> This occurs if one sets a Flex default rule
> . { return yytext[0]; }
> and the lexer finds a stray UTF-8 byte.

I would say that here, you return a char (yytext[0]) with "a high bit set", on 
an architecture where char is signed, so you are actually returning a negative 
int (when the 8th bit is set).  And for Bison, any negative token number stands 
for end-of-file.

You should actually write:

. { return (unsigned char) yytext[0]; }


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