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bug_null_debuginfo.ll
; RUN: llc < %s

!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!2}

!0 = distinct !DICompileUnit(language: DW_LANG_C99, isOptimized: false, emissionKind: FullDebug, file: !1, globals:  null)
!1 = !DIFile(filename: "t", directory: "")
!2 = !{i32 1, !"Debug Info Version", i32 3}