[Dwarf-Discuss] PROPOSAL: Constant expressions in location lists

[Robinson, Paul T NonStop]

A tangential question regarding DW_AT_location...

Alexandre Oliva wrote:

> The effect would be equivalent to that of adding a deref to
> each piece of each DW_AT_location location expression that mentions a
> memory address, except that DW_AT_location locations are assumed to be
> modifiable (and thus exclusively assigned to the mentioned variable),
> whereas a dereferenced address or a register in a DW_AT_value is
> expected to be non-modifiable or shared.

I didn't think DW_AT_location locations must be "exclusively assigned."
Copy propagation could cause multiple variables to be assigned to the
same machine location simultaneously, and their DWARF descriptions
should accurately reflect that.  (Modifying one variable implicitly
modifies the other.)  Did I misunderstand something?

--paulr