[PATCH] Fix null pointer dereference

[Simon Marchi]

On 2020-02-21 1:35 a.m., Ruslan Kabatsayev wrote:
> This restores the check that demangle is non-null, that was removed
> (inadvertently, I suppose) by commit
> 43816ebc335481c99808c4fdfffb9ea3f510b19a.
> 
> gdb/ChangeLog
> 2020-02-21  Ruslan Kabatsayev  <b7.10110111@gmail.com>
> 
> 	* dwarf2/read.c (dwarf2_name): Fix null pointer dereference
> ---
>  gdb/dwarf2/read.c | 7 ++++---
>  1 file changed, 4 insertions(+), 3 deletions(-)
> 
> diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
> index f998fe6b8d0..1fd5f55a534 100644
> --- a/gdb/dwarf2/read.c
> +++ b/gdb/dwarf2/read.c
> @@ -21752,11 +21752,12 @@ dwarf2_name (struct die_info *die, struct dwarf2_cu *cu)
>  
>  	  /* Avoid demangling DW_STRING (attr) the second time on a second
>  	     call for the same DIE.  */
> +	  gdb::unique_xmalloc_ptr<char> demangled;
>  	  if (!DW_STRING_IS_CANONICAL (attr))
> -	    {
> -	      gdb::unique_xmalloc_ptr<char> demangled
> -		(gdb_demangle (DW_STRING (attr), DMGL_TYPES));
> +	    demangled.reset (gdb_demangle (DW_STRING (attr), DMGL_TYPES));
>  
> +	  if (demangled)
> +	    {
>  	      const char *base;
>  
>  	      /* FIXME: we already did this for the partial symbol... */
> -- 
> 2.16.2
> 

Hi Ruslan,

This patch here fixes the same issue, I believe:

https://sourceware.org/ml/gdb-patches/2020-02/msg00490.html

It should be committed soon.

Simon