[Bug c++/67875] missing -Warray-bounds in a default placement new expression, bogus location on an overload

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67875

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
      Known to work|                            |6.1.0
         Resolution|---                         |DUPLICATE
           Assignee|unassigned at gcc dot gnu.org      |msebor at gcc dot gnu.org
      Known to fail|                            |5.3.0

--- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> ---
With -Wplacement-new, GCC issues a diagnostic for the buffer overflow in the
invocation of the placement new expression (with or without optimization).  It
doesn't issue a -Warray-bounds warning but that problem is being tracked in bug
67872 so I'll close this as a duplicate of bug 67942.

$ cat y.C && /build/gcc-trunk-git/gcc/xgcc -B /build/gcc-trunk-git/gcc -O2 -S
-xc++ -Warray-bounds y.C
void* operator new (__SIZE_TYPE__, void *p) { return p; }

struct A {
    char a [4];
} a;

void foo ()
{
    new (&a.a [5]) char;
}
y.C: In function ‘void foo()’:
y.C:9:10: warning: placement new constructing an object of type ‘char’ and size
‘1’ in a region of type ‘char [4]’ and size ‘0’ [-Wplacement-new=]
     new (&a.a [5]) char;
          ^~~~~~~~

*** This bug has been marked as a duplicate of bug 67942 ***