From: Sigurd <cu9ypd@...>
Date: 2012-06-22T16:35:31+09:00
Subject: Re: How to debug ruby source code using gdb?, can't print array content

Ruby has GDB helpers. Take a look at https://github.com/ruby/ruby/blob/trunk/.gdbinit
Fo instance rp prints any ruby value. There are other handy helpers as well. 

On Jun 22, 2012, at 7:55 AM, gmspro gmspro wrote:

> I tried something like this in array.c
> 
> rb_ary_initialize(int argc, VALUE *argv, VALUE ary)
> {
>  long len;
>  int ln;
>  int *ar;
>  VALUE size, val;
>  switch (TYPE(ary)) {
>    case T_FIXNUM:
>      break;
>    case T_STRING:
>      break;
>    case T_ARRAY:
>      ar=RARRAY(ary);
>      ln=RARRAY_LEN(ary);
>      printf("ln: %d\n",ln);
>      ar=RARRAY_PTR(ary);
>      break;
>    default:
>      rb_raise(rb_eTypeError, "not valid value");
>      break;
>  }
> 
> 
> gdb ./ruby
> (gdb)run
> ctrl+c
> (gdb)break array.c:rb_ary_initialize
> (gdb)continue
> arr=Array.new(3)
> arr[0]=5
> arr[1]=7
> ctrl+d
> (gdb)next
> 
> But i can't understand how to print the value using printf(); in
> array.c:rb_ary_initialize function doing some casting.
> 
> Can anyone post reply with example to do it?
> 
> https://github.com/ruby/ruby/blob/0b0dea752c0ef35d1a964b812a1a7fd033ab9e2e/README.EXT#L125
> 
> https://github.com/ruby/ruby/blob/0b0dea752c0ef35d1a964b812a1a7fd033ab9e2e/array.c#L569
> 
> Thanks.
> 
> -- 
> Posted via http://www.ruby-forum.com/.
>