[all-commits] [llvm/llvm-project] ad5fad: [LTO] Suppress emission of empty combined module b...

[Zakk Chen via All-commits]

  Branch: refs/heads/master
  Home:   https://github.com/llvm/llvm-project
  Commit: ad5fad0ac56b78a692a052f2da397b4bc7fd6150
      https://github.com/llvm/llvm-project/commit/ad5fad0ac56b78a692a052f2da397b4bc7fd6150
  Author: Zakk Chen <zakk.chen at sifive.com>
  Date:   2020-05-04 (Mon, 04 May 2020)

  Changed paths:
    M lld/COFF/LTO.cpp
    M lld/ELF/LTO.cpp
    M lld/test/COFF/lto-obj-path.ll
    M lld/test/COFF/pdb-thinlto.ll
    M lld/test/ELF/lto/linker-script-symbols-assign.ll
    M lld/test/ELF/lto/thinlto-obj-path.ll
    M llvm/include/llvm/LTO/Config.h
    M llvm/include/llvm/LTO/LTO.h
    M llvm/lib/LTO/LTO.cpp
    M llvm/test/ThinLTO/X86/empty-module.ll
    M llvm/test/tools/gold/X86/thinlto.ll
    M llvm/tools/gold/gold-plugin.cpp

  Log Message:
  -----------
  [LTO] Suppress emission of empty combined module by default

Summary:
That unless the user requested an output object (--lto-obj-path), the an
unused empty combined module is not emitted.

This changed is helpful for some target (ex. RISCV-V) which encoded the
ABI info in IR module flags (target-abi). Empty unused module has no ABI
info so the linker would get the linking error during merging
incompatible ABIs.

Reviewers: tejohnson, espindola, MaskRay

Subscribers: emaste, inglorion, arichardson, hiraditya, simoncook, MaskRay, steven_wu, dexonsmith, PkmX, dang, lenary, s.egerton, luismarques, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D78988