AFAIK this could've been fixed in LLVM a long time ago, which would also help C code compiled with clang, although I believe stack probes are opt-in there.

We can't fix it fully in rustc because we don't know the stack size, which can grow with aggressive inlining, for example.

I suppose we could summarily probe allocas we know are larger than the page size, which would solve this particular situation (one large variable), but it's not a panacea.