RE: Can't Print Two Dimensional Array Element for Fortran

[lylelyle]

Setting language to c works. Yes, the subscript numbers are a little  bit wired: the row number is from 0, and the column number is from 1. This doesn't like C or Fortran.

Thanks,
Lyle

> Date: Sat, 24 Apr 2010 04:08:18 +0200
> From: address@hidden
> To: address@hidden
> CC: address@hidden
> Subject: Re: Can't Print Two Dimensional Array Element for Fortran
>
> On Fri, Apr 23, 2010 at 08:22:40PM -0500, lylelyle wrote:
> >
> > No, I can't do this in gdb.
> >
> > (gdb) print a(4)
> > Wrong number of subscripts
> >
> > (gdb) print a(6,1)
> > no such vector element
> >
> > lyle
> >
>
> I'm, quite sorry. As gdb relies on language features, you might either examine
> the memory directly (calculating the address by hand):
>
> (showing the second step):
> (gdb) x/5f &a
> 0x7fffffffd360: 1 0 -9.05608908e+33 4.59163468e-41
> 0x7fffffffd370: -4.65473378e+33
> (gdb) x/5f 0x7fffffffd374
> 0x7fffffffd374: 2 0 0 -nan(0x7fd4c8)
> 0x7fffffffd384: 4.59163468e-41
>
> or more convenient switch the language to C: be carefull: the colummn numbers
> are calculated from 1 up, as the first element a[0][0] is skipped internally.
> I once knew why, but I can't remember why.
>
> (gdb) set language c
> (gdb) p a
> $32 = {{1, 4, -9.05608908e+33, 4.59163468e-41, -4.65473378e+33}, {2, 5, 0,
> -nan(0x7fd4c8), 4.59163468e-41}, {3, 6, 1.40129846e-45, 0, -4.65251539e+33}}
> (gdb) p a[2][2]
> $33 = 6
>
> of course you can always get back to fortran again:
>
> (gdb) set language fortran
> (gdb) p a
> $36 = (( 1, 4, -9.05608908e+33, 4.59163468e-41, -4.65473378e+33) ( 2, 5, 0,
> -nan(0x7fd4c8), 4.59163468e-41) ( 3, 6, 1.40129846e-45, 0, -4.65251539e+33) )
>
> bye ingo

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