https://issues.dlang.org/show_bug.cgi?id=24449

          Issue ID: 24449
           Summary: immutable data can be mutated after initialization in
                    shared static constructor
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: nick@geany.org

import std.stdio;

immutable int x;

shared static this()
{
    x = 5; // OK, initialization not assignment
    x.writeln(); // 5
    x = 6; // should error
    x++; // should error
    assert(x == 7);
}

It should not be possible to assign immutable data after it is initialized in the shared static constructor. That would make those consistent with class constructors:

class C
{
    immutable int x;
    this()
    {
        x = 5;
        x = 6; // error, x initialized multiple times
    }
}

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