This is an error position in asm.js code that is reported differently.

Minimized repro:
var asm = (function() {
  "use asm";
  function f(x, y) {
    return x - y;
  }
  return f;
})();
obj = {};
obj.__defineGetter__('toString', () => null);
asm(obj);


With no args:
test.js:4: TypeError: Cannot convert object to primitive value
    return x - y;
             ^

With --always-opt:
test.js:3: TypeError: Cannot convert object to primitive value
  function f(x, y) {
            ^


I thought I saw that before, but I fail to find it.
Michi, can you take a look please?

Yes, this is tracked by  issue 733693 . It's a WontFix for the AstGraphBuilder and will be fixed by the new asm.js validator.

ClusterFuzz has detected this issue as fixed in range 47276:47277.

Detailed report: https://clusterfuzz.com/testcase?key=5442274740928512

Fuzzer: foozzie_js_mutation
Job Type: v8_foozzie
Platform Id: linux

Crash Type: V8 correctness failure
Crash Address: 
Crash State:
  configs: x64,ignition:x64,ignition_turbo_opt
  sources: c4f
  
Sanitizer: address (ASAN)

Regressed: V8: 43536:43537
Fixed: V8: 47276:47277

Reproducer Testcase: https://clusterfuzz.com/download?testcase_id=5442274740928512

See https://github.com/google/clusterfuzz-tools for more information.

If you suspect that the result above is incorrect, try re-doing that job on the test case report page.