Using ... in an overloaded function causes fatal error

[JohnAlbin]

If you try to use the variable argument indicator, ..., inside an overloaded function, it will work just fine in Ruby Sass, but libSass will throw an error. For example, rgba() can be called with either 4 params ($red, $green, $blue, $alpha) or with 2 params ($hex, $alpha).

input.scss

// Use the 2 parameter form of rgba().
$params: #fff .5;
test {
  color: rgba($params...);
}

libSass 3.3.6

overloaded function `rgba` given wrong number of arguments on line 4 at column 10

ruby sass 3.4.21

test {
  color: rgba(255, 255, 255, 0.5);
}

version info:

$ node-sass --version
node-sass   3.10.1  (Wrapper)   [JavaScript]
libsass     3.3.6   (Sass Compiler) [C/C++]

The error is thrown from this line: https://github.com/sass/libsass/blob/master/src/eval.cpp#L834

[JohnAlbin]

I found a simpler test case that didn't require using call(), so I've updated the above test case and the bug description. Both the old and the new test case produce the same error message.