Esprima Mangle bug?

I've narrowed down a bug to when I use Esprima's Mangle to shorten variable names (other minification options don't generate the error).

I'm seeing an error in the Bangle emulator when I execute this:

// works fine
g.clear();

function dothis() {
  g.clear();
}

function test(one, two, three, four, five) {
  let arrTmp = 0; //new Uint8Array(12);
  for(let i=0; i<1; i++) {}
  
  // fails
  g.clear();
  dothis();
}

test();

I'm getting this error:

>Uncaught Error: Function "clear" not found!
 at line 1 col 23
let a=0;for(let g=0;g<1;g++);g.clear(),dothis()
                               ^
in function "test" called from line 1 col 92
...(),dothis()}g.clear(),test()
                              ^

You can see that it changed the loop variable to 'g' , which should still be a local variable, but it clearly affects Bangle's 'g'.

However, if you do any one of the following, the error goes away and the Bangle 'g' is fine:

• if you comment out g.clear() and use the "dothis()" function instead
  
• if you comment out the "let arrTmp" assignment
  
• if you comment out the empty for loop
  
• if you reduce the argument list to 4 items
  
  

Just thought I'd share; not sure whether this is an Esprima bug, or an interpreter bug (a "let g=" within a for loop should be its own scope and not interfere with global context?)