llvm/llvm/test/tools/llvm-nm/undefined-only.test

# RUN: yaml2obj %s -o %t.o
# RUN: llvm-nm --undefined-only %t.o | FileCheck %s --implicit-check-not=symbol_defined

!ELF
FileHeader:
  Class:   ELFCLASS64
  Data:    ELFDATA2LSB
  Type:    ET_REL
  Machine: EM_X86_64
Sections:
  - Name: .text
    Type: SHT_PROGBITS
Symbols:
  - Name:    symbol_undefined_a
  - Name:    symbol_defined
    Section: .text
  - Name:    symbol_undefined_b

# CHECK:      U symbol_undefined_a
# CHECK-NEXT: U symbol_undefined_b