Assertion failed: ((CGF.CurFuncDecl == nullptr || CGF.Builder.getIsFPConstrained() || isa<CXXConstructorDecl>(CGF.CurFuncDecl) || isa<CXXDestructorDecl>(CGF.CurFuncDecl) || (NewExceptionBehavior == llvm::fp::ebIgnore && NewRoundingBehavior == llvm::RoundingMode::NearestTiesToEven)) && "FPConstrained should be enabled on entire function"), function ConstructorHelper, file /usr/src/contrib/llvm-project/clang/lib/CodeGen/CodeGenFunction.cpp, line 165.

[pkubaj]

FreeBSD 14.0-CURRENT
LLVM 16.0.6
powerpc64le, powerpc64, powerpc

Reproducer:

template <class Compare> void stable_sort(int last, Compare) {
  stable_sort(last, int());
}
#pragma STDC FENV_ACCESS ON
struct cluster_result {
  int operator[](int);
};
template <int> void generate_SciPy_dendrogram() {
  cluster_result Z2;
  int trans_tmp_1(0);
  int trans_tmp_2 = Z2[1];
  stable_sort(trans_tmp_1, trans_tmp_2);
}
void linkage_wrap() { generate_SciPy_dendrogram<false>; }

Build with:

/usr/bin/c++ -cc1 -triple powerpc-unknown-freebsd14.0 -emit-obj fastcluster_python-684654.cpp

Output:

Assertion failed: ((CGF.CurFuncDecl == nullptr || CGF.Builder.getIsFPConstrained() || isa<CXXConstructorDecl>(CGF.CurFuncDecl) || isa<CXXDestructorDecl>(CGF.CurFuncDecl) || (NewExceptionBehavior == llvm::fp::ebIgnore && NewRoundingBehavior == llvm::RoundingMode::NearestTiesToEven)) && "FPConstrained should be enabled on entire function"), function ConstructorHelper, file /usr/src/contrib/llvm-project/clang/lib/CodeGen/CodeGenFunction.cpp, line 165.

[VoxSciurorum]

I confirmed this behavior with the system compiler on FreeBSD 14.0-CURRENT on amd64 and aarch64 as well. The ports build of llvm16 does not crash, despite being based on a very similar version of llvm.

[pkubaj]

LLVM in ports has assertions disabled, which is probably the reason.

[VoxSciurorum]

LLVM in ports has assertions disabled, which is probably the reason.

I think you are right about that. I also reproduced the crash on amd64 Linux using a build with assertions enabled.

[DimitryAndric]

This regressed with 65cf77d by @spavloff (cc @rjmccall).

[spavloff]

The reproducer provided here is not related to 65cf77d, because it causes compiler crash with that commit reverted.

The problem reported here is fixed by the patch https://reviews.llvm.org/D154359.