Here we die because we do not have variable constructor in LTO stream because the variable was optimized out at compile time already. Do we still need to build RTL here? We can easily check for optimized out vars...
But if we need a placeholder RTL, I suppose most practical variant would be to avoid get_variable_section from ICEing for those optimized out vars and just assume something (it is all about decision whether the var will be in rodata/rodata.rel or rodata.rel.local - definitely not relevant for dwarf2out)
