message: [boost][python3] Fix building with VS 2019
diff: @@ -12,6 +12,7 @@ namespace vcpkg::VisualStudio
  static constexpr CStringView V_120 = "v120";
  static constexpr CStringView V_140 = "v140";
  static constexpr CStringView V_141 = "v141";
  + static constexpr CStringView V_142 = "v142";
  struct VisualStudioInstance
  {
  @@ -213,35 +214,62 @@ namespace vcpkg::VisualStudio
  for (const fs::path& subdir : msvc_subdirectories)
  {
  + auto toolset_version_full = subdir.filename().u8string();
  + auto toolset_version_prefix = toolset_version_full.substr(0, 4);
  + CStringView toolset_version;
  + std::string vcvars_option;
  + if (toolset_version_prefix.size() != 4)
  + {
  + // unknown toolset
  + continue;
  + }
  + else if (toolset_version_prefix[3] == '1')
  + {
  + toolset_version = V_141;
  + vcvars_option = "-vcvars_ver=14.1";
  + }
  + else if (toolset_version_prefix[3] == '2')
  + {
  + toolset_version = V_142;
  + vcvars_option = "-vcvars_ver=14.2";
  + }
  + else
  + {
  + // unknown toolset minor version
  + continue;
  + }
  const fs::path dumpbin_path = subdir / "bin" / "HostX86" / "x86" / "dumpbin.exe";
  paths_examined.push_back(dumpbin_path);
  if (fs.exists(dumpbin_path))
  {
  - const Toolset v141_toolset{
  - vs_instance.root_path, dumpbin_path, vcvarsall_bat, {}, V_141, supported_architectures};
  + Toolset toolset{vs_instance.root_path,
  + dumpbin_path,
  + vcvarsall_bat,
  + {vcvars_option},
  + toolset_version,
  + supported_architectures};
  const auto english_language_pack = dumpbin_path.parent_path() / "1033";
  if (!fs.exists(english_language_pack))
  {
  - excluded_toolsets.push_back(v141_toolset);
  - break;
  + excluded_toolsets.push_back(std::move(toolset));
  + continue;
  }
  - found_toolsets.push_back(v141_toolset);
  + found_toolsets.push_back(std::move(toolset));
  if (v140_is_available)
  {
  - const Toolset v140_toolset{vs_instance.root_path,
  + found_toolsets.push_back({vs_instance.root_path,
  dumpbin_path,
  vcvarsall_bat,
  {"-vcvars_ver=14.0"},
  V_140,
  - supported_architectures};
  - found_toolsets.push_back(v140_toolset);
  + supported_architectures});
  }
  - break;
  + continue;
  }
  }
  