Re: frames / stacks / source? was Re: coverage/profiling

[Han-Wen Nienhuys]

Ludovic Courtès escreveu:
> Hi,
> 
> Han-Wen Nienhuys <address@hidden> writes:
> 
>> address@hidden info]$ guile
>> guile> (trap-enable 'enter-frame-handler)
>> throw from within critical section.
>> Abortado
> 
> Same here with HEAD and 1.8.0.  Here's what happens:
> 
>   #0  0x0fc13f6c in raise () from /lib/tls/libc.so.6
>   #1  0x0fc15a0c in abort () from /lib/tls/libc.so.6
>   #2  0x0ffa4a1c in scm_ithrow (key=0x10015410, args=0x300a2558, 
> noreturn=<value optimized out>) at throw.c:699
>   #3  0x0ff3718c in scm_error_scm (key=0x10015410, subr=0x300781f0, 
> message=0x300781d0, args=0x300a2578, data=0x4) at error.c:92
>   #4  0x0ff37220 in scm_error (key=0x10015410, subr=<value optimized out>, 
> message=0xffc5594 "Unknown option name: ~S", args=0x300a2578, 
>       rest=0x4) at error.c:58
>   #5  0x0ff37268 in scm_misc_error (subr=0xfa <Address 0xfa out of bounds>, 
> message=0x3001bb60 "", args=0x0) at error.c:268
>   #6  0x0ff721a8 in scm_options (args=0x300a25e8, options=0xffe1b40, n=7, 
> s=0xffc117c "evaluator-traps-interface") at options.c:202
>   #7  0x0ff3a1e4 in scm_evaluator_traps (setting=0x300a25c8) at eval.c:3134
>   #8  0x0ff3ec50 in deval (x=<value optimized out>, env=0x300a2668) at 
> eval.c:4219
> 
> (Note the "Unknown option name"...)

I have added 

 /* the jump buffer data structure */
@@ -695,7 +696,24 @@ scm_ithrow (SCM key, SCM args, int noret
 
   if (scm_i_critical_section_level)
     {
+      SCM s = args;
+      int i = 0;
+
+      /*
+       We have much better routines for displaying Scheme, but we're
+       already inside a pernicious error, and it's unlikely that they
+       are available to us. We try to print something useful anyway,
+       so users don't need a debugger to find out what went wrong.
+       */
       fprintf (stderr, "throw from within critical section.\n");
+      if (scm_is_symbol (key))
+       fprintf (stderr, "error key: %s\n", scm_i_symbol_chars (key));
+
+      
+      for (; scm_is_pair (s); s = scm_cdr (s), i++)
+       if (scm_is_string (scm_car (s)))
+         fprintf (stderr, "argument %d: %s\n", i, scm_i_string_chars (scm_car 
(s)));
+      
       abort ();
     }
 

I wonder, is there any generic routine for safely printing immediates 
and strings/symbols?  This might also be a good idea to apply to 1.8.
With lilypond, we occasionally have this problem as well, and it's
a PITA to have to use a debugger to find out about a user-level fault.


 
-- 
 Han-Wen Nienhuys - address@hidden - http://www.xs4all.nl/~hanwen