Optional linker-synthetic symbols are only created if they are undefined
in the final output.
This test is for a regression where an explicit --export of an lazy archive
symbol caused an undefined reference to an optional symbol to occur *after*
the optional symbols were created.

RUN: llvm-mc -filetype=obj -triple=wasm32-unknown-unknown %p/Inputs/start.s -o %t.o
RUN: llvm-mc -filetype=obj -triple=wasm32-unknown-unknown %p/Inputs/optional-symbol.s -o %t.a1.o
RUN: rm -f %t.a
RUN: llvm-ar rcs %t.a %t.a1.o
RUN: wasm-ld --export=get_optional %t.o %t.a -o %t.wasm
RUN: obj2yaml %t.wasm | FileCheck %s

CHECK:      FunctionNames:
CHECK-NEXT:   - Index:           0
CHECK-NEXT:     Name:            _start
CHECK-NEXT:   - Index:           1
CHECK-NEXT:     Name:            get_optional