If "struct Relative" is defined at the outer of doTest(), everything is OK.

Here are the test codes:
=====================================
import std.stdio;

void doTest()
{
    struct Relative
    {
        int xBase;
        int xDir;

        // This method causes a compiler internal error
        void MoveTo()
        {
        }
    }

    Relative rel = {1, 2};
}

int main(string[] args)
{
    return 0;
}
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