The following program:

function foo(anon xs: [i64]) {}

function main() {
    let xs = [0; 5]
    foo(xs[2..4])
}

fails to compile in the c++ stage with the following error:

build/test.cpp:13:1: error: no matching function for call to 'foo'
foo(((xs).slice_range(static_cast<i64>(2LL), static_cast<i64>(4LL))));
^~~
build/test.cpp:5:13: note: candidate function not viable: no known conversion from 'ArraySlice<long long>' to 'const Array<i64>' (aka 'const Array<long long>') for 1st argument
static void foo(const Array<i64> xs) {
            ^
1 error generated.