https://issues.dlang.org/show_bug.cgi?id=19785

          Issue ID: 19785
           Summary: const basic types in function parameters should not
                    mangle as const
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Severity: minor
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: bugzilla@digitalmars.com

void foo(const int i) { }
  void bar(int i) { }

Mangles as:

  _D4test3fooFxiZv
  _D4test3barFiZv

The 'x' is not necessary in the mangling for foo(), as the const would only
apply to the internal behavior of foo(), and is not relevant to the caller.

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