https://issues.dlang.org/show_bug.cgi?id=20728

          Issue ID: 20728
           Summary: There is third way to create immutable data
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dlang.org
          Assignee: nobody@puremagic.com
          Reporter: porton@narod.ru

https://dlang.org/spec/const3.html says that there are two ways of "Creating immutable data".

I disagree, there is also the third way:

auto int x = 1;
void f(ref immutable int r) { }
f(x);

This is neither literal nor cast to immutable data. It is the third way.

See also https://forum.dlang.org/post/lgkgcpxeyfrmuqlmigge@forum.dlang.org as a hint about the issue whether it actually creates immutable data.

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