[Bug libstdc++/103848] [11/12 Regression] std::deque<>::iterator operator- uses "0" for nullptr check, triggers "zero-as-null-pointer-constant" warning

[jakub at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103848

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |jakub at gcc dot gnu.org

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I said - int(__x._M_node != _Map_pointer())
but indeed one doesn't know from looking at the code that it is comparison
against NULL.
Other options perhaps could be - (__x._M_node ? 1 : 0) or - 1 + !__x._M_node
or - !!__x._M_node
I'd hope the compiler treats all those the same, if not, we have something to
fix.