AaronBallman 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.
Thank you for the help, that does pass all the tests, so I've added a commit for it. 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
