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From: "gomfy via 9fans" <9fans@9fans.net>
To: 9fans <9fans@9fans.net>
Subject: [9fans] How to generate a "debuggable" lex.yy.c?
Date: Wed, 10 Nov 2021 14:28:02 -0500	[thread overview]
Message-ID: <16365724820.70ECFff3.198950@composer.9fans.topicbox.com> (raw)

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Hello,                                                                         
                                                                               
I would like to generate a lexer with debug functionality. I'm relying on a slightly modified versions of the sources:
https://9fans.github.io/plan9port/man/man3/bio.html                            
https://9fans.github.io/plan9port/man/man1/yacc.html                           
https://9fans.github.io/plan9port/man/man1/lex.html                            
                                                                               
As far as I can tell, my issues are not related to the fact that I'm working with a slightly modified version, but I thought I'll mention it just to be on the safe side.
                                                                                    
The first issue was that the debug information collected in fdebug was not flushed and as a result the **y.debug** file for the lexer kept showing up empty. I had to add Bterm(fdebug); at the end of the main() in **yacc.c** to get the **y.debug** file to be generated with content.
                                                                               
Now, my issue is that if I'm compiling the generated **lex.yy.c** with -DLEXDEBUG I get: 

undefined reference to `allprint(char)' 

because of sections like the one below:
                                                                               
# ifdef LEXDEBUG                                                               
            if(debug){                                                              
                fprintf(yyout,"char ");                                             
                allprint(yych);                                                     
                putchar('\n');                                                      
                }                                                                   
# endif                                                                             
                                                                                    
The allprint() function is defined in the Lex source **sub1.c**.  It seems I'd have to link against the Lex source to be able to compile **lex.yy.c** in debug mode, which would be a bit complicated as there are some clashes with my other application. Other complications are caused by the global variables that show up in allprint() and other functions that are listed in the DEBUG section of **sub1.c**.
                                                                               
Can someone point me in the right direction, or tell me what am I missing here?
                                                                                    
Thanks!                                                                        
Gyorgy    
------------------------------------------
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             reply	other threads:[~2021-11-10 19:28 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-11-10 19:28 gomfy via 9fans [this message]
2021-11-11 11:25 ` Charles Forsyth
2021-11-11 15:26   ` gomfy via 9fans

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