Add flag at prep stage to OMIT_DEPRECATED

[skliper]

Need an easy way for users (and the CI system) to omit all deprecated elements. Something like

make OMIT_DEPRECATED=true prep

which would then internally add all the -DCFE_OMIT_DEPRECATED -DOSAL_OMIT_DEPRECATED and so on flags when building everything.

[skliper]

Imported from trac issue 324. Created by jhageman on 2019-08-23T17:07:17, last modified: 2019-08-23T17:07:17

[skliper]

@jphickey do you have a suggestion for this one? I quickly jammed in:

  # Omit deprecated elements if set
  if (OMIT_DEPRECATED)
    add_definitions(-DCFE_OMIT_DEPRECATED_6_6 -DOSAL_OMIT_DEPRECATED)
  endif (OMIT_DEPRECATED)

to the prepare function of mission_build.cmake so I could move forward with CI improvements locally. Didn't cache but easy enough to add.

[jphickey]

I recommend just setting OSAL_USER_C_FLAGS when doing the initial prep, which allows one to add your own flags.

i.e. make SIMULATION=native OSAL_USER_C_FLAGS='-DCFE_OMIT_DEPRECATED_6_6 -DOSAL_OMIT_DEPRECATED -Wall -Werror -std=c99 -pedantic' prep

Shouldn't need to edit files. This is how I generally test it out. This is also cached so it is retained as part of the build tree.

[skliper]

I am really not a fan of doing it that way. OSAL_USER_C_FLAGS is not consistently applied everywhere, I think I've either emailed you or commented somewhere about previous issues with this technique. I'd much rather from a top level add these definitions explicitly, and not require the user or CI to know what the actual define values are.

[skliper]

See #24 for some other issues with OSAL_USER_CFLAGS. Not a fan of make SIMULATION=native OSAL_USER_C_FLAGS='-DCFE_OMIT_DEPRECATED_6_6 -DOSAL_OMIT_DEPRECATED -Wall -Werror -std=c99 -pedantic' prep since a layer of abstraction (like "OMIT_DEPRECATED") means I wouldn't have to retrain users whenever a flag changes or we decide to add or remove from the warning set. Also allows us to work towards compliance (define an initial set, and add as needed) with only requiring to update in one spot... we've discussed strict-protoypes and cast-align in the past.