[bug] Abort option isn't working

[DieMyst]

For example, there https://webassembly.studio/?f=ayvoyj2s81 if we run build, this warning will occur:
WARN: Unknown option '--use abort='''
and this error on run:
[error]: LinkError: WebAssembly Instantiation: Import #0 module="env" function="abort" error: function import requires a callable

[dcodeIO]

The correct syntax there is

  asc.main([
    ...
    "--use", "abort=",
  ], callback);

but this will then lead to an assertion error of ERROR: missing abort because the compiler expects that at least some abort routine is present that it can use.

Adding a custom abort to main.ts and using that instead of the built-in abort should work, though:

function myAbort(
  message: string | null,
  fileName: string | null,
  lineNumber: u32,
  columnNumber: u32
): void {}

  asc.main([
    ...
    "--use", "abort=main/myAbort",
  ], callback);

In this case, whenever an abort happens, the custom function will be called right before a trap occurs. If that function does nothing, optimizing the module should remove it as dead code.

[MaxGraey]

@dcodeIO I tried "--use", "abort=" but this caused to WARN: Unknown option '--use abort=' and doesn't have effect.

https://webassembly.studio/?f=u15n0gyad7

[dcodeIO]

When I run "Build" there, I get ERROR: missing abort. The error you mention would match "--use abort=" as a single argument, not two.

[dcodeIO]

Might well be that this worked differently in earlier versions of the compiler, and allowing the user to disable the abort routine entirely instead of having to provide an alternative seems like something worth to support.

[MaxGraey]

It seems this should be:

for (let [name, alias] of globalAliases) {

instead:

assemblyscript/src/program.ts

Line 829 in f9a77b1

for (let [alias, name] of globalAliases) {

[dcodeIO]

Consider --use Math=NativeMath. There, Math is the alias and NativeMath the internal name to be aliased. Should be correct this way.

[MaxGraey]

Hmm, but here using globalAliases[name] = alias:

assemblyscript/src/index.ts

Line 99 in 0484a6b

globalAliases.set(name, alias);

[dcodeIO]

Yeah, the naming is off there, but the order is not changed. name and alias should be switched there I think.

[dcodeIO]

PR linked above should fix all of this :)

[MaxGraey]

Great! Also will be great mention how use abort properly in docs I guess :)

[dcodeIO]

Added here: https://docs.assemblyscript.org/details/debugging#overriding-abort