Here's a snippet of the method.
```
void Lowerer::LowerBoundCheck(IR::Instr *const instr)
{
...
if(rightOpnd->IsIntConstOpnd())
{
IntConstType newOffset;
if(!IntConstMath::Add(offset, rightOpnd->AsIntConstOpnd()->GetValue(), &newOffset)) <<--- (a)
{
offset = newOffset;
rightOpnd = nullptr;
offsetOpnd = nullptr;
}
}
...
if(!rightOpnd)
{
rightOpnd = IR::IntConstOpnd::New(offset, TyInt32, func);
}
}
```
At (a), it uses "IntConstMath::Add" to check integer overflow. But the size of IntConstType equals to the size of pointer, and the "offset" variable is used as a 32-bit integer. So it may fail to check integer overflow on 64-bit system.
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