Fix: signed integer overflow

[illusory0x0]

The main difficulty in fixing this bug is locating it.
If we need to separate pull requests, I'll do that, but the process of fixing bugs is unlikely to be separated.

• chore: add sanitizer in native backend #1605
• signed integer overflow in native backend #1594
• undefined behavior: left shift of negative value in native backend #1608

[coveralls]

Pull Request Test Coverage Report for Build 5221

Details

• 8 of 8 (100.0%) changed or added relevant lines in 4 files are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.03%) to 85.775%

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Files with Coverage Reduction	New Missed Lines	%
builtin/iter.mbt	2	84.62%

Totals
Change from base Build 5218:	-0.03%
Covered Lines:	5439
Relevant Lines:	6341

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💛 - Coveralls

[illusory0x0]

this is another issus.

• use zero instead of literal 0.0 #1558

D:\a\core\core\target\native\debug\test\builtin\builtin.blackbox_test.c(198789): error C2124: divide or mod by zero

[Guest0x0]

the -fwrapv flag should be passed to C compiler when compiling C generated by MoonBit. So signed integer overflow is not UB in MoonBit. But the hasher should indeed use UInt instead of Int, so that part may still be an improvement (in terms of code readability)

[illusory0x0]

FTR: gcc option -fwrapv