Merge topic 'modules-better-messages' 571b5e1f2c cxxmodules: improve error messages for C++ module setup 8b4d32c18b cmStandardLevelResolver: add query for the effective standard level 17ddc4ac76 cmStandardLevelResolver: compare with static string literals 6f1dae2b01 cmStandardLevelResolver: use `cmStrCat` where possible 0d45d40e13 cmStandardLevelResolver: use character literals where possible Acked-by: Kitware Robot <kwrobot@kitware.com> Tested-by: buildbot <buildbot@kitware.com> Merge-request: !8755