Binaryen.js default stack size might be too low

[dcodeIO]

Recently, a bunch of strange issues have appeared in conjunction with Binaryen.js builds, yielding runtime errors like

• RuntimeError: null function or function signature mismatch and
• TypeError: c(...) is not a function

as described in more detail in https://github.com/AssemblyScript/assemblyscript/issues/2682 and https://github.com/AssemblyScript/assemblyscript/pull/2683.

After getting debug builds to work again as outlined in https://github.com/WebAssembly/binaryen/issues/5647, it turned out that the __assert_fail in

 function wasm__Visitor_wasm__PrecomputingExpressionRunner_2c_20wasm__Flow___visit_28wasm__Expression__29($0, $1, $2) {
  $0 = $0 | 0;
  $1 = $1 | 0;
  $2 = $2 | 0;
  var $5 = 0, $6 = 0, $21 = 0;
  $5 = __stack_pointer - 16 | 0;
  __stack_pointer = $5;
  HEAP32[($5 + 12 | 0) >> 2] = $0;
  HEAP32[($5 + 8 | 0) >> 2] = $1;
  HEAP32[($5 + 4 | 0) >> 2] = $2;
  $6 = HEAP32[($5 + 8 | 0) >> 2] | 0;
  label$1 : {
   if ((HEAP32[($5 + 4 | 0) >> 2] | 0 | 0) != (0 | 0) & 1 | 0) {
    break label$1
   }
   __assert_fail(95448 | 0, 113524 | 0, 58 | 0, 78548 | 0);
   wasm2js_trap();
  }
  ...

is hit, looking like a stack overflow or so is the underlying cause. The surrounding stack trace indicates that there is a longer sequence of PrecomputingExpressionRunner::visits, further substantiating the assumption:

RuntimeError: memory access out of bounds
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c7d4)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ConstantExpressionRunner<wasm::PrecomputingExpressionRunner>::visitLocalSet(wasm::LocalSet*) (wasm://wasm/38a29666:wasm-function[97299]:0x13f3674)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eea11)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ConstantExpressionRunner<wasm::PrecomputingExpressionRunner>::visitLocalSet(wasm::LocalSet*) (wasm://wasm/38a29666:wasm-function[97299]:0x13f3674)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eea11)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ConstantExpressionRunner<wasm::PrecomputingExpressionRunner>::visitLocalSet(wasm::LocalSet*) (wasm://wasm/38a29666:wasm-function[97299]:0x13f3674)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eea11)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visitBinary(wasm::Binary*) (wasm://wasm/38a29666:wasm-function[97322]:0x140c815)
▌     at wasm::Visitor<wasm::PrecomputingExpressionRunner, wasm::Flow>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97277]:0x13eebdd)
▌     at wasm::ExpressionRunner<wasm::PrecomputingExpressionRunner>::visit(wasm::Expression*) (wasm://wasm/38a29666:wasm-function[97271]:0x13edc3d)
▌     at invoke_viii (file://path/to/binaryen_wasm.js:7802:29)

And indeed, when increasing stack size to -sSTACK_SIZE=655360, the errors go away in both debug and release builds, so my guess is that the default stack size of 65536 is a little low.

[kripken]

That seems likely, yes. Emscripten lowered the default stack size to 64K recently, which is usually enough, but Binaryen does do some deep recursions. Avoiding recursion might be useful in the long term, but for now we should increase the default stack size in Binaryen. The old 5MB is probably fine as binaryen.js doesn't need to run in highly-constrained memory environments AFAIK.