Method GetPchSource

Source/cmGeneratorTarget.cxx:3117–3175

}

std::string cmGeneratorTarget::GetPchSource(std::string const& config,
                                            std::string const& language,
                                            std::string const& arch) const
{
  if (language != "C" && language != "CXX" && language != "OBJC" &&
      language != "OBJCXX") {
    return std::string();
  }
  auto const inserted =
    this->PchSources.insert(std::make_pair(language + config + arch, ""));
  if (inserted.second) {
    std::string const pchHeader = this->GetPchHeader(config, language, arch);
    if (pchHeader.empty()) {
      return std::string();
    }
    std::string& filename = inserted.first->second;

    cmGeneratorTarget const* generatorTarget = this;
    cmGeneratorTarget const* reuseTarget = this->GetPchReuseTarget();
    bool const haveReuseTarget = reuseTarget && reuseTarget != this;
    if (reuseTarget) {
      generatorTarget = reuseTarget;
    }

    filename =
      cmStrCat(generatorTarget->GetCMFSupportDirectory(), "/cmake_pch");

    // For GCC the source extension will be transformed into .h[xx].gch
    if (!this->Makefile->IsOn("CMAKE_LINK_PCH")) {
      std::map<std::string, std::string> const languageToExtension = {
        { "C", ".h.c" },
        { "CXX", ".hxx.cxx" },
        { "OBJC", ".objc.h.m" },
        { "OBJCXX", ".objcxx.hxx.mm" }
      };

      filename = cmStrCat(filename, arch.empty() ? "" : cmStrCat('_', arch),
                          languageToExtension.at(language));
    } else {
      std::map<std::string, std::string> const languageToExtension = {
        { "C", ".c" }, { "CXX", ".cxx" }, { "OBJC", ".m" }, { "OBJCXX", ".mm" }
      };

      filename = cmStrCat(filename, arch.empty() ? "" : cmStrCat('_', arch),
                          languageToExtension.at(language));
    }

    std::string const filename_tmp = cmStrCat(filename, ".tmp");
    if (!haveReuseTarget) {
      {
        cmGeneratedFileStream file(filename_tmp);
        file << "/* generated by CMake */\n";
      }
      cmFileTimes::Copy(pchHeader, filename_tmp);
      cmSystemTools::MoveFileIfDifferent(filename_tmp, filename);
    }
  }
  return inserted.first->second;