[Issue 20608] New: [REG2.087] Cannot pass tuple.expand to auto ref T... template argument pack

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=20608

          Issue ID: 20608
           Summary: [REG2.087] Cannot pass tuple.expand to auto ref T...
                    template argument pack
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: regression
          Priority: P1
         Component: dmd
          Assignee: nobody at puremagic.com
          Reporter: johanengelen at weka.io

Testcase:
```
void foo(T...)(auto ref T args) {}

void main() {
    import std.typecons;
    enum tup = tuple(1,"jojo");
    foo(tup.expand); // line 6
}
```

This errors with DMD >= 2.087 with:
onlineapp.d(6): Error: cannot modify constant expression `Tuple(1,
"jojo").__expand_field_0`

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