I'm trying to make PyCall.jl compatible with PackageCompiler.jl in JuliaPy/PyCall.jl#651. This branch itself has been working. You can check it with

julia -e 'using Pkg; pkg"dev PyCall"'
cd ~/.julia/dev/PyCall/
git remote add -f tkf https://github.com/tkf/PyCall.jl
# git checkout -b aot tkf/aot
git checkout -b aot 65eb0c04453420946c6e33d24d885f1cfa7578d0
aot/compile.jl --color=yes

However, merging JuliaPy/PyCall.jl#668

git merge --no-edit v1.91.0
aot/compile.jl --color=yes

breaks AOT-compilation with the following error (sandwiched by some logging messages and a stacktrace):

Invalid bitcast
  %56 = bitcast i64 %55 to %jl_value_t addrspace(64)*, !dbg !413904
LLVM ERROR: Broken function found, compilation aborted!

(Here is an example of the full output: https://travis-ci.org/JuliaPy/PyCall.jl/jobs/511050638#L761-L763)

Does this mean there is a function in JuliaPy/PyCall.jl#668 that invokes a bug in Julia compiler? How do I debug more?

cc: @stevengj