[Bug tree-optimization/87314] pointless comparison of malloc result to a string not eliminated

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87314

--- Comment #8 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #7)
> Is it safe with -fmerge-all-constants if the decls are TREE_READONLY?

I don't think DECL vs STRING_CST is any special here (or well, STRING_CSTs
will end up in mergeable string sections).  It's probably more a question
for

const int a = 2;
const int b = 2;

int main() { return &a != &b; }

which we "miscompile" since forever with -fmerge-all-constants.