[Bug analyzer/94355] support for C++ new expression

["dmalcolm at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94355

--- Comment #4 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
(In reply to Ivan Sorokin from comment #0)
> At the moment static analyzer warns about leaked malloc. It would be great
> if C++ new expression were also supported.
> 
> Example:
> 
> void f()
> {
>     char* p = new char;
> }
> 
> Expected diagnostic:
> 
> warning: leak of 'p' [CWE-401] [-Wanalyzer-malloc-leak]
> 
>     3 |     char* p = new char;

Actual diagnostic with commit
r11-3090-g1690a839cff2e0276017a013419d81d675bbf69d:

demo.cc: In function ‘void f()’:
demo.cc:4:1: warning: leak of ‘p’ [CWE-401] [-Wanalyzer-malloc-leak]
    4 | }
      | ^
  ‘void f()’: events 1-2
    |
    |    3 |     char* p = new char;
    |      |                   ^~~~
    |      |                   |
    |      |                   (1) allocated here
    |    4 | }
    |      | ~                  
    |      | |
    |      | (2) ‘p’ leaks here; was allocated at (1)
    |

where the diagnostic's location is at the point where "p" goes out of scope. 
There's an argument that it would be better emitting it at the "new".