Re: Dynamic array bounds problem

[Jan Kratochvil <jan dot kratochvil at redhat dot com>]

Hi Jonas,

On Wed, 24 Dec 2008 11:11:12 +0100, Jonas Maebe wrote:
> struct {
>   intptr_t refcount;
>   intptr_t high;
>   char data[1];
> } dynarr_t;
>
> A dynamic array variable is always a pointer which is either NULL (not  
> allocated) or which points to the "data" field of the above struct (so  
> the length and refcount are at negative offsets). The lower bound is  
> always 0, the current upper bound is stored in the "high" field.

Just be sure DW_TAG_variable's DW_AT_location gives the address of the pointer
to dynaddr_t, not the pointer value itself.


> When I change the language in gdb from Pascal to Fortran it still prints 

The patch works even for C variable-length-arrays, it is mostly invoked by
check_typedef().  Still there were missing some check_typedef()s at some
places of the Fortran support part of GDB.


> I'm new to git (I know cvs and svn) so I'm not sure what the proper way 
> is to identify the revision I'm using, but the last commit in my git log 
> is f2deac9fa3dfd4d9010e3590963ded5f0d56fe0a

This GIT tag should work (although there is an update now).  You should check
that TYPE_DYNAMIC is present in the sources.


> Any hints on what I might be doing wrong?

Some basic hints can be given by `set debug target 1' to at least see which
addresses are being read while evaluating the array boundaries.


> I can provide a compiled program if required.

Yes, interested in checking it as the DWARF dump above looks fine to me.


Regards,
Jan