Segfault in ctor-eval when optimizing an imported table of funcrefs

[stevenfontanella]

I ran the following example from main to see whether the no-op function call would get optimized away:

;; repro.wast
;; bin/wasm-ctor-eval --ctors=test repro.wast
(module
  (import "env" "table" (table $t 1 funcref))
  (type $v (func))
  (func $target (type $v)
    (nop)
  )
  (elem (table $t) (i32.const 0) func $target)

  (func $test
    (call_indirect $t (type $v) (i32.const 0))
  )
  (export "test" (func $test))
)

Unlike other similar issues, this one does import from env which is expected to work.

From checking lldb, the crash is from dereferencing null in tableSize: link. Maybe this is related to the comment immediately above?