https://issues.dlang.org/show_bug.cgi?id=15660

          Issue ID: 15660
           Summary: result of pure function
           Product: D
           Version: D2
          Hardware: x86_64
                OS: Linux
            Status: NEW
          Severity: normal
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: iaktakh@gmail.com

Compiler can't determine result of pure function is not unique

import std.stdio;

struct S
{
    void[] arr; // with int instead of void program doesn't compiles

    auto f() pure @safe
    {
        int[] a = new int[4];
        arr = a;
        return a;
    }
}
void main() @safe
{
    S s;
    immutable a = s.f();
    int[] b = (cast(int[])s.arr);
    writeln(a); // [0, 0, 0, 0]
    b[0] = 1;
    writeln(a); // [1, 0, 0, 0]
}

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