clang::CodeGen::CGBuilderTy::CreateStructGEP crash: Assertion `Idx < NumElements && "Invalid element idx!"' failed. (llvm/IR/DataLayout.h)

[eridys]

I'm experiencing a crash in

clang++: llvm-project/llvm/include/llvm/IR/DataLayout.h:653: 
uint64_t llvm::StructLayout::getElementOffset(unsigned int) const: 
Assertion `Idx < NumElements && "Invalid element idx!"' failed.

According to "How to submit an LLVM bug report" this seems to be a "middle-end optimization bug" - test-case.bc.gz attached.

clang version 15.0.6 (https://github.com/llvm/llvm-project.git e6e61e9b2ef7c0fa3fe2cd7c612e00ecf57a9dd8)
Target: x86_64-unknown-linux-gnu

(applies to any prior 15.* version, too)

Note: one peculiarity I use during compilation is the option --unsigned-char on a x86-64 system.

[EugeneZelenko]

Could you please provide reproducer? https://godbolt.org should be helpful.

[eridys]

Bugpoint trace
Clang trace

After creduce I could also reproduce it on https://godbolt.org/z/9s75vrfPx

[llvmbot]

@llvm/issue-subscribers-clang-codegen

[Fznamznon]

https://reviews.llvm.org/D142534 that was originally made as an attempt to fix #60166 helps here as well.