Insta crash on Hermes but works with JSC

[alexandrius]

Hey friends 👋,

I recently enabled this library in a project. Everything seemingly went through until I enabled Hermes engine. The app crashes immediately after launching with error:

error: Execution was interrupted, reason: EXC_BAD_ACCESS (code=1, address=0x0).
The process has been returned to the state before expression evaluation.

I found out that the issue happens in either of these methods BN_bn2lebinpad, BN_bn2binpad:

react-native-bignumber/cpp/MGBigNumberHostObject.cpp

Lines 138 to 145 in 56873d9

	if (le)
	{
	BN_bn2lebinpad(thiz->bign, ab.data(runtime), len);
	}
	else
	{
	BN_bn2binpad(thiz->bign, ab.data(runtime), len);
	}

Here's value of ab:

What I tried so far:

• I commented out toArrayLike (inside commonjs/BigNumber.js) below here but weirdly the issue is still there. I wasn't able to find any toArrayLike invocations anywhere else

react-native-bignumber/src/BigNumber.ts

Lines 247 to 252 in 56873d9

	native.toArrayLike.call(
	this.internalBigNum,
	res.buffer,
	endian === 'le',
	len || -1
	);

• If I wrap if(ab.data(runtime) != NULL) the issue goes away but application doesn't behave correctly.

I would appreciate any suggestions.
Thanks!

[mrousavy]

oh weird, maybe we use ArrayBuffer wrong, Hermes should have native support for that.... cc @Szymon20000

[kewde]

Hermes doesn't allocate any memory for an ArraysBuffer's dataBuffer if the size is 0. It's a nullpointer.. The code also doesn't check if the ArrayBuffer size is sufficiently large to carry the BigNumber's data and potentially overflows.

[JuanRdBO]

Any news on this? I would be excited to implement this library into my app. But this exact same issue is causing my app to insta-crash as well.

[mordonez-me]

Hello guys, do you guys have plans for fixing this bug? I am having an insta-crash like this:

[JuanRdBO]

I'm having the same crash as above as well with @solana/web3.js

[alexandrius]

To everyone struggling with this issue. I recommend migrating to BigInt