https://issues.dlang.org/show_bug.cgi?id=23378

          Issue ID: 23378
           Summary: ImportC: dynamic array alias imported by C treated as
                    pointer when used as function parameter.
           Product: D
           Version: D2
          Hardware: All
                OS: All
            Status: NEW
          Keywords: ImportC
          Severity: minor
          Priority: P1
         Component: dmd
          Assignee: nobody@puremagic.com
          Reporter: dave287091@gmail.com

Below is for a 64bit target:
// s.d
alias String = const(char)[];

// x.c
__import s;

_Static_assert(sizeof(String) == 16, "");
String bar;
_Static_assert(sizeof(bar) == 16, "");

void foo(String a){
    _Static_assert(sizeof(a) == 16, ""); // this fails
    const char* b = a; // this compiles, which implies the arg is just a
const(char)*
}

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