https://issues.dlang.org/show_bug.cgi?id=18984

          Issue ID: 18984
           Summary: Debugging stack struct's which are returned causes
                    incorrect debuginfo.
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Windows
            Status: NEW
          Severity: major
          Priority: P1
         Component: visuald
          Assignee: nobody@puremagic.com
          Reporter: turkeyman@gmail.com

Created attachment 1704
  --> https://issues.dlang.org/attachment.cgi?id=1704&action=edit
Test case

>From the prior conversation:

> Debugging issues:
>    Stack allocated struct won't show values correctly (repro project attached)
>    Supply metadata0.bin as commandline arg
>    Place watch at lines 91 and 119, step and watch the values of `Frame f` and `Packet p` as they are populated with data
>    Notice that those stack structs do not appear to be changing, and show rubbish values.


You can see the actual value in the hidden return value __HID1/__HID2 (you can see the symbol in the disassembly). dmd seems to ignore RVO when emitting the debug info.

--