On ELF platforms, the instrumentation registers global variables using
`__asan_register_elf_globals` for the default `UseGlobalsGC` case. If
all instrumented global variables in a module are discarded by linker
GC, we will have `start == stop`.
Normally `start == 0`, but `start != 0` is possible with a linker script
retaining `asan_globals`. The called `__asan_register_globals` would
access out-of-bounds `globals[n-1]`, though there is likely no runtime
failure.
Pull Request: https://github.com/llvm/llvm-project/pull/96529