https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92634
--- Comment #13 from Alan Modra <amodra at gmail dot com> --- Yes, I came to the conclusion myself that this is really nothing to do with dereferencing. So my original claim and Andrew's replies about dereferencing are not relevant. The standard says of unary & "The operand of the unary & operator shall be either a function designator, the result of a [] or unary * operator, or an lvalue that designates an object that is not a bit-field and is not declared with the register storage-class specifier." We don't have a function designator, the result of a [] or unary *, so the & operand must be an lvalue. Of lvalues, the standard says (in part): "if an lvalue does not designate an object when it is evaluated, the behavior is undefined" And that along with lack of a special case for &p->f is the language reason why the binutils code was UB.
