spirv-opt assertion failure related to OpCopyObject #3547
Description
spirv-opt with -O fails with:
spirv-opt: ../source/opt/def_use_manager.cpp:61: void spvtools::opt::analysis::DefUseManager::AnalyzeInstUse(spvtools::opt::Instruction*): Assertion `def && "Definition is not registered."' failed.
The SPIR-V applies OpCopyObject to an id with void type, which is a dumb thing to do but valid according to the current spec.
Issue found using spirv-fuzz.