We currently have a number of formulae that use CMAKE_INSTALL_RPATH set to lib or opt_lib. This breaks relocatability on macOS. For example, see 52203dd, and its parent, 068fcb9.

Instead, CMAKE_INSTALL_RPATH should be set to @loader_path/../lib, but only on macOS, as @loader_path is macOS-specific.

Example PRs: #75450, #75449, #75457.

Formulae that use CMAKE_INSTALL_RPATH:

• abseil abseil: make bottle relocatable #75450
• aom aom: make bottle relocatable #75457
• assimp assimp: make bottle relocatable #75881
• bullet bullet: make bottle relocatable #75882
• cmark-gfm cmark-gfm: make bottle relocatable #75883
• cryptominisat cryptominisat: make bottle relocatable #75884
• csound csound: make bottle relocatable #75566
• f3d f3d: make bottle relocatable #75886
• gdcm gdcm: make bottle relocatable #75887
• grpc abseil 20210324.1 #75928
• itk
• ktoblzcheck
• libical libical: make bottle relocatable #76740
• libzzip libzzip: make bottles relocatable, update license #76745
• mavsdk abseil 20210324.1 #75928
• mlpack mlpack: make bottles relocatable #77376
• mongo-c-driver mongo-c-driver: make bottles relocatable #77377
• mongo-cxx-driver mongo-cxx-driver: use #rpath #77703
• mosquitto mosquitto: use #rpath #77704
• ngt ngt: use #rpath #78095
• opencascade opencascade: use #rpath #77715
• opencolorio opencolorio: use #rpath #78098
• openmama openmama: use #rpath #78116
• ospray ospray: use #rpath #78118
• physfs physfs: use #rpath #78205
• pyside pyside 6.2.1 #89084
• pyside@2
• rabbitmq-c rabbitmq-c: use #rpath #78214
• rdkit
• sfml sfml: make bottle relocatable #75449
• standardese standardese 0.5.2 #76423
• uriparser uriparser: use #rpath #78218
• vtk vtk: use #rpath #78220
• vtk@8.2
• x265 x265: make bottle relocatable #76432
• xerces-c xerces-c: use #rpath #78221
• xrootd xrootd: use #rpath #78222
• zstd zstd: make bottle relocatable #75880

I imagine I'll get through this list eventually, but help would be appreciated.

Bonus, for settings CMAKE_EXE_LINKER_FLAGS:

• rocksdb rocksdb: make bottle relocatable #75879