[LTP] flex warnings

[Dan K. <da...@ke...>]

I'm having a look at the compiler warnings in an ltp build,
and the first thing that shows up is a huge blort of flex
warnings of the form

"scan.l", line 111: warning, dangerous trailing context
"scan.l", line 133: warning, dangerous trailing context
"scan.l", line 160: warning, dangerous trailing context
"scan.l", line 171: warning, dangerous trailing context
"scan.l", line 179: warning, dangerous trailing context
"scan.l", line 236: warning, dangerous trailing context
"scan.l", line 97: warning, dangerous trailing context

This warning is described at
http://www.gnu.org/manual/flex-2.5.4/html_node/flex_23.html :
"Some trailing context patterns cannot be properly matched
and generate warning messages ("dangerous trailing context").
These are patterns where the ending of the first part of the
rule matches the beginning of the second part, such as
"zx*/xy*", where the 'x*' matches the 'x' at the
beginning of the trailing context. (Note that the POSIX
draft states that the text matched by such patterns is
undefined.)"

Looking at scan.l, though, it's hard to see what flex is
complaining about.  The pattern in line 97 is
^<<<rts_keyword_start>>>$
The pattern at line 236 is
<OUT>^.+$
I'm no lex expert, so I don't quite see how those
are ambiguous.

Anyone know what's up with those warnings?

Thanks,
Dan


-- 
Dan Kegel
http://www.kegel.com
http://counter.li.org/cgi-bin/runscript/display-person.cgi?user=78045