Comment (by Roland Haas):

This changes the way option lists behave, so should be reconsidered only after the May 2022 release since it requires use of LD_XXX_FLAGS to set settings that were previously inherited from CPPFLAGS and CXXFLAGS on the linker line.

The branch also has the unrelated commit https://bitbucket.org/cactuscode/cactus/commits/f04408489af6800ad8d5e177eabd9c4a53acc1fd which is not strictly related to the subject of the ticket and instead disallows multiple definitions with pgCC by defatul in the same manner that gcc starting with version 10 does (-fno-common is the default in gcc10 and up).

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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2553/cactus-link-command-uses-cppflags-and