tbaederr wrote: > @tbaederr -- this triggers an assertion with the new constexpr interpreter in > `clang/test/AST/Interp/intap.cpp` but I'm not certain I understand why. Can > you help me figure out how to fix that? > > https://buildkite.com/llvm-project/github-pull-requests/builds/56785#018ef1ee-1e9c-48be-8944-0bce2c6f441d/6-1940
In `IntegralAP::truncate()` (which we call when getting the `3` and setting it as the value of the bitfield), we actually truncate the bitwith of the underlying `IntAP`, not just the _value_. This fixes things for me: ```diff diff --git a/clang/lib/AST/Interp/IntegralAP.h b/clang/lib/AST/Interp/IntegralAP.h index bab9774288bf..fb7ee1451571 100644 --- a/clang/lib/AST/Interp/IntegralAP.h +++ b/clang/lib/AST/Interp/IntegralAP.h @@ -154,7 +154,10 @@ public: } IntegralAP truncate(unsigned BitWidth) const { - return IntegralAP(V.trunc(BitWidth)); + if constexpr (Signed) + return IntegralAP(V.trunc(BitWidth).sextOrTrunc(this->bitWidth())); + else + return IntegralAP(V.trunc(BitWidth).zextOrTrunc(this->bitWidth())); } IntegralAP<false> toUnsigned() const { ``` I'd push this (it doesn't break any existing tests), but I'm not 100% sure if this is the right way to do that. Also, I should follow up with a `truncate` -> `truncateValue` rename. https://github.com/llvm/llvm-project/pull/89254 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits