[patch] Add guard to build_reconstructed_reference

[Richard Biener]

On August 16, 2019 3:44:36 PM GMT+02:00, Eric Botcazou <ebotcazou@adacore.com> wrote:
>Hi,
>
>this adds a small guard to the new function
>build_reconstructed_reference for 
>broken VIEW_CONVERT_EXPRs.  Users can easily generate these in Ada
>through the 
>generic function Ada.Unchecked_Conversion and they need to be
>accepted...
>
>Tested on x86_64-suse-linux, OK for the mainline?

Ok. 

Richard. 

>
>2019-08-16  Eric Botcazou  <ebotcazou@adacore.com>
>
>	* tree-sra.c (build_reconstructed_reference): Return NULL_TREE instead
>	of NULL.  Add guard for broken VIEW_CONVERT_EXPRs.
>
>
>2019-08-16  Eric Botcazou  <ebotcazou@adacore.com>
>
>	* gnat.dg/opt81.ad[sb]: New test.