https://issues.dlang.org/show_bug.cgi?id=15653

          Issue ID: 15653
           Summary: IFTI fails for immutable parameter
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: major
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: john.loughran.colvin@gmail.com

% cat test.d
void foo(T)(const T x) {}
void bar(T)(immutable T x) {}

void main()
{
    foo(4); // OK
    bar(4); // Error
}
% dmd test.d
test.d(8): Error: template test.bar cannot deduce function from argument types
!()(int), candidates are:
test.d(3):        test.bar(T)(immutable T x)

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