Re: [bug-gawk] mixed LF/CRLF scripts: incorrect line numbers

[Jannick]

I just checked that the error report is just fine for pure LF or CRLF
versions of the file.

This makes me wonder how gawk processes EOLs, since I was expecting
a bit of a mess with a pure LF file which did (surprisingly) does happen.

To make this meaningful here gawk's signature I am working with and I
forgot to mention yesterday: 
GNU Awk 4.2.1, API: 2.0 (GNU MPFR 4.0.1-p6, GNU MP 6.1.2)

Many thanks,
J.

On Mon, 7 May 2018 17:15:02 +0200, Jannick wrote:
> Hi All,
> 
> I have come across something weird from the EOL hell on my Windows box 
> using Cygwin's gawk in -D mode (debug). Gawk did not show the correct 
> line numbers which caused confusion in break statements.
> 
> Drilling things down I found out this is because the script file is of 
> mixed EOL type (LF and CRLF).  The culprit lines are those with LF 
> only (at least on my CRLF Windows machine using the cygwin's LF gawk
version).
> 
> In the syntax error report gawk tells us the line numbers of the 
> processed script it thinks they are OK and supposedly uses throughout 
> the program (syntax errors, debug etc.). So I used the attached file with
a small example.
> 
> The sample file is CRLF with one single CR line causing the issue. 
> Running it produces
> 
> gawk: ./gawk-line.awk:2:        line2 .= 2 # shown with correct line
> gawk: ./gawk-line.awk:2:              ^ syntax error
> gawk: ./line4 .= 4 # shown with line 3!= 3 # not shown, here the 
> comment-tag syntactically meant as EOL does not help
> gawk: ./gawk-line.awk:3:              ^ syntax error
> gawk: ./gawk-line.awk:4:        line5 .= 5 # shown with line 4!
> gawk: ./gawk-line.awk:4:              ^ syntax error
> 
> The problem starts in line 3. Before that gawk and I agreed so far.
> - line 3 is ignored, the CR causes the overlay in the syntax error of 
> the next line, the comment tag does not stop gawk from parsing beyond 
> the CR, I think
> - line 4 gawk thinks it is line 3, but we think it is line 4 ... and so
on.
> 
> I included the syntax error report in the attached file.
> 
> I think this is a bug, albeit it lives in the CR/CRLF realm where the 
> best solution would not be to point to a private compilation of gawk 
> on my Windows notebook to avoid cygwin's executable and CR confusion.
> 
> 
> Please give me a shout if I you need any more information or I should 
> run any tests here on my machine.
> 
> Best - and sorry for being a bit lengthy in this posting, J.