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src: fix integer overflow in GetNow #22214

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src: fix integer overflow in GetNow #22214

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2 changes: 1 addition & 1 deletion src/env.cc
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Original file line number Diff line number Diff line change
Expand Up @@ -617,7 +617,7 @@ Local<Value> Environment::GetNow() {
CHECK_GE(now, timer_base());
now -= timer_base();
if (now <= 0xffffffff)
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Should this have an U suffix…?

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It shouldn't matter in this case, right? I thought they were equivalent since this won't fit into an int and the next type is unsigned int.

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Okay, I looked it up – without the suffix it is still signed, but it’s a long int in that case, so we’re probably fine here. :)

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Does this mean that the bug still exists for numbers in 2^31 .. 2^32 range?

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@nkbt This PR fixed the bug for those numbers – all others should remain the same

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Thanks, I was not sure if NewFromUnsigned does exactly that

return Integer::New(isolate(), static_cast<uint32_t>(now));
return Integer::NewFromUnsigned(isolate(), static_cast<uint32_t>(now));
else
return Number::New(isolate(), static_cast<double>(now));
}
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