Fix tests to use Bits::Signed for 128-bit extremes - #154
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Literal hex numbers are treated as bitvectors, and the tests
constructed the min 128-bit integer by negating an unsigned value:
let min_128 := -Std::Bits::Unsigned(0x8000_0000_0000_0000_0000_0000_0000_0000);
However, Bits::Unsigned(0x80...00) already gives -2**127 (the minimum).
Negating it produces 2**127 which overflows __int128 in the C23 backend:
min_128 = ((__int128)(- ((__int128)((unsigned __int128)((unsigned __int128)0x80000000000000000000000000000000uwb)))));
Use Bits::Signed and drop the negation. This avoids the overflow and
expresses the intended values better.
nikolaykosarev
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Without this change, the tests fail (locally) for me. Unclear yet why they did not fail at PR testing at #148 ... |
alastairreid
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Jul 29, 2026
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Literal hex numbers are treated as bitvectors, and the tests
constructed the min 128-bit integer by negating an unsigned value:
However, Bits::Unsigned(0x80...00) already gives -2**127 (the minimum).
Negating it produces 2**127 which overflows __int128 in the C23 backend:
Use Bits::Signed and drop the negation. This avoids the overflow and expresses the intended values
better.