[Bug tree-optimization/43565] Missed address comparison folding of DECL_COMMONs

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43565

--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
That optimization is of course possible if the compiler can prove the addresses
are different.  So, e.g. if one of the two vars is defined locally, or both
locally, or one is automatic and another namespace/file scope, etc.