Re: [PATCH] Avoid indexing std::vector past the end

[Simon Marchi <simon.marchi@polymtl.ca>]

On 2017-12-30 14:31, Ruslan Kabatsayev wrote:
> The code here wants to find address of an element, and often this
> element is one past the end of std::vector. Dereferencing that element
> leads to undefined behavior, so it's better to simply use pointer
> arithmetic instead of taking address of invalid dereference.
> 
> gdb/ChangeLog:
> 
> 	* psymtab.c (recursively_search_psymtabs): Use pointer arithmetic
> 	instead of dereferencing std::vector past the end.

Hi Ruslan,

The patch LGTM, with a nit I missed the first time.  Please push with 
that fixed.

> ---
>  gdb/psymtab.c |    8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/gdb/psymtab.c b/gdb/psymtab.c
> index c87ef25..c622f4c 100644
> --- a/gdb/psymtab.c
> +++ b/gdb/psymtab.c
> @@ -1337,21 +1337,21 @@ recursively_search_psymtabs
>      }
> 
>    partial_symbol **gbound
> -    = &objfile->global_psymbols[ps->globals_offset + 
> ps->n_global_syms];
> +    = objfile->global_psymbols.data() + ps->globals_offset + 
> ps->n_global_syms;

Space before parentheses, here and in the other lines.

Thanks,

Simon