[Bug c++/86176] Wnull-dereference warning disappears with a call to std::cout on the line after

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86176

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2018-06-18
     Ever confirmed|0                           |1

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
The warning depends on inlining which makes it require -O2 in your case and
with the cout line uncommented the inlining doesn't take place because of cost
reasons.  Making f static shows

> g++-7 t.C -O2 -Wnull-dereference
t.C: In function ‘int main()’:
t.C:6:11: warning: null pointer dereference [-Wnull-dereference]
     printf("%d\n", *i);
     ~~~~~~^~~~~~~~~~~~
t.C:7:19: warning: null pointer dereference [-Wnull-dereference]
     std::cout << *i;
                   ^

so confirmed but the issues are by design.  GCC isn't a static analyzer.