- Eg, with surface writers now in surfMesh, there are fewer libraries
  depending on conversion and sampling.

COMP: regularize linkage ordering and avoid some implicit linkage (#1238)

- change internal naming from 'EXE_EXT' to 'EXT_EXE' for symmetry with
  'EXT_SO'

- fix typo in makefiles/info that affected wmake -show-compile-c

- additional safeguard in src/OpenFOAM/Make/options against self-linking.
  This is not normally required unless PROJECT_LIBS has been added into
  the link stage.

- replace (darwin) with (__APPLE__)
- replace (solarisGcc) with (__sun__ && __GNUC__)
- instead of 'darwin' -> '__APPLE'

- cease with passing a -D$(WM_ARCH) define since this adds no useful
  additional information and isn't used anywhere.

Reference
http://nadeausoftware.com/articles/2012/01/c_c_tip_how_use_compiler_predefined_macros_detect_operating_system

--

COMP: Extend size disambiguation on long (#1238)

- allows better separation from compiler settings

- use -fPIC instead of legacy -KPIC for intel compiler

solaris:
  - rename WM_ARCH from SunOS to solaris64 for consistency with wmake/rules
  - drop non-64 solaris from wmake/rules
  - remove automatic selection of FJMPI. This should be done in the bashrc
    or prefs.sh file instead.
  - remove old (likely inaccurate) exported flags, rely on wmake -show-xyz
    or user config instead

darwin:
  - remove '-Ddarwin' from the exported WM_CFLAGS, WM_CXXFLAGS.
    Not used elsewhere (ThirdParty)

- with the wmake rules we may have some compiler options bound to the
  internal compiler variable. For example,

     CC  = g++ -std=c++11 -m64

     c++FLAGS = ...

  So shift any flags from CC to CXXFLAGS for the output of
  'wmake -show-cxx', 'wmake -show-cxxflags', etc.

  This makes it much easier to handle the values correctly elsewhere.
  Eg,

      CXX="$(wmake -show-cxx)" CXXFLAGS="$(wmake -show-cxxflags)" \
         ./configure

- provide dedicated detection 'have_ptscotch' function that can be
  used after the 'have_scotch' function.

  It sets the PTSCOTCH_ARCH_PATH, PTSCOTCH_INC_DIR, PTSCOTCH_LIB_DIR
  and helps when the serial and parallel versions are located with
  different logic.

- add an additional test for wmake pre-processing

- can be useful for retrieving the compilation flags for use with other
  make systems (eg, cmake)

  * wmake -show-compile   (C++ not C)
  * wmake -show-cxx
  * wmake -show-cxxflags

- relocates some logic from makefiles/general into platform-specific
  overrides

- with -mcpu=native for automatic detection and -armpl for linking in
  the performance libraries

STYLE: relocate -mcpu into compiler instead of compiler-flags (#1225)

- with -mcpu=native for automatic detection and -armpl for linking in
  the performance libraries

- in addition to managing different vendors and versions, it may also
  be necessary or desirable to have a particular variant
  (eg, profiling, release, etc).

  Devise a new meaningful name for the variant and create a
  corresponding wmake rule.

  Eg, SYSTEMOPENMPI-profiling with a corresponding
      "wmake/rules/linux64Gcc/mplibSYSTEMOPENMPI-profiling" file
  that has suitable content for your system.

CONFIG: intel-mpi use intel64/ paths only for config and wmake rules (#1153)

- previously adjusted the config files, but missed the changes
  required for the wmake rules too.

  Now simply migrate to using  "intel64/{include,bin,lib}"
  instead of the older naming  "{include,bin,lib}64"

  These changes work since at least intel-mpi 2015 (5.x), but possibly
  earlier as well

- was WM_PROJECT_API in the environment and FOAM_API in dictionaries.

  Make these both consistently FOAM_API.
  This is a non-breaking change, since the value of WM_PROJECT_API
  (added in 1812) and/or FOAM_API is purely informative.
  For the current correct values, always use

    * foamEtcFile -show-api
    * wmakeBuildInfo -show-api

- Note: mpich now builds libmpi.so instead of libmpich.so

- define both -DMPICH_SKIP_MPICXX and -DOMPI_SKIP_MPICXX regardless of
  using openmpi or mpich. This simplifies the files and does not harm.

  - objectRegistry search, erase methods
  - clip, minMax
  - function object triggering
  ...

- older emacs tools into legacy
- old process tools

* Less frequently used scripts into bin/tools/

  - findEmptyMake
  - foamAllHC
  - foamUpdateCaseFileHeader

* Infrastructure file (only used by foamNewApp)

  - wmake/wmakeFilesAndOptions -> wmake/scripts/wmakeFilesAndOptions

* Merge wmakeRoot convenience as 'wmake -pwd'
* Remove obsolete wmakePrintBuild (superseded by wmakeBuildInfo)
* Remove unused mergeHistory file

- instead of

      WM_COMPILER=GccKNL WM_COMPILE_OPTION=Opt

      -> linux64GccKNLDPInt32Opt

  now specify

      WM_COMPILER=Gcc  WM_COMPILE_OPTION=OptKNL

      -> linux64GccDPInt32OptKNL

This makes it easier (and more obvious) for adding different tweaks
without needing to generate too many files.
Eg,

    cd wmake/rules/linux64Gcc

    cp cOpt   cOptBdw
    cp c++Opt c++OptBdw

    edit these two files and then use WM_COMPILE_OPTION=OptBdw

CONFIG: provide some default c/c++ flags in General compiler rules

- can make is easier when deriving new compile options, and ensures
  that '-02' is enabled as an initial default.

- finds the correct root directory location before creating
  the lnInclude directory

  Eg,

  from within something like src/finiteVolume/fields/fvPatchFields/..

      wmakeLnInclude -update -root

  it backtracks to find the top-level directory with Make/
  and makes the lnInclude directory there:

    Using /home/mark/openfoam/OpenFOAM-plus/src/finiteVolume
        ln: /home/mark/openfoam/OpenFOAM-plus/src/finiteVolume/lnInclude

- was for parallel compilation across multiple hosts, but less useful
  with modern CPUs with higher number of cores and/or hyperthreading.

  Fragile use and dependent on a 'lockfile' utility that is not often
  installed.

- use local 'prefix' variable for easier override and more consistency

- was WM_PROJECT_API in the environment and FOAM_API in dictionaries.

  Make these both consistently FOAM_API.
  This is a non-breaking change, since the value of WM_PROJECT_API
  (added in 1812) and/or FOAM_API is purely informative.
  For the current correct values, always use

    * foamEtcFile -show-api
    * wmakeBuildInfo -show-api

- looks slightly messier without associative arrays, but improves
  portability. Should now also work with dash.

STYLE: support wmakeBuildInfo -cmp and -check options as equivalent

- backend settings for scan-build

STYLE: generalize rule for obtaining compiler stem

- primarily for handling cmake replacement libraries