- less efficient and less portable than using single-pass processing

- easier to ensure that flags are consistent

- downgrades some diagnostics about nonconformant code from errors to
  warnings. Oddly enough, the errors actually arise from STL library
  elements shipped with gcc itself. Affects kahip compilation with
  gcc-6, gcc-7

- primary points for an external user are the polyMesh constructor

- add config info for gcc-7.3.0

COMP: intel-2017. Ignore unknown pragmas. Disambiguate method resolution.

- sentinel was not working properly when building user-space routines

- required if there is no system openmp and libomp or libgomp are
  only found in the clang hierarchy

STYLE: add some notes in the openmp rules.

- the _OPENMP macro is now used in low-level testing files

- allows enabling new warnings without causing messy output with older
  clang versions

- initial settings for ADIOS2, linuxARM64Gcc, linuxARM64Clang

- unknown options or missing option values now emit a shorter message
  without the entire usage. This makes it easier to identify the errors
  and is better aligned with the behaviour of GNU system tools.

  ====
     $ simpleFoam -case
     Using: OpenFOAM-plus (see www.OpenFOAM.com)
     Build: plus-01234

     Error: option '-case' requires an argument

     See 'simpleFoam -help' for usage
  ====

- provide for reduced (-help) and full (-help-full) usage information.
  In many cases the reduced usage provided sufficient and easier
  to find the information.

- make -srcDoc an alias for -doc-source

- no warnings about option aliases for future dates.

- add -compiler=NAME option to remove a build or platforms directory
  corresponding to any specified compiler on the current arch.

- when -compiler or -compiler=NAME is specified, also clean related
  sub-directories as well. This will cleanup mpi-related directory.

- the USE_OMP preprocessor symbol is also defined with the openmp
  compile flag to allow conditional compilation of openmp-specific
  code.

- improve functional compatibility with DynList (remove methods)
  * eg, remove an element from any position in a DynamicList
  * reduce the number of template parameters
  * remove/subset regions of DynamicList

- propagate Swap template specializations for lists, hashtables

- move construct/assignment to various containers.

- add find/found methods for FixedList and UList for a more succinct
  (and clearer?) usage than the equivalent global findIndex() function.

- simplify List_FOR_ALL loops

- the cray C/C++ compilers appear to be option-compatible with gcc.

- no wmake rules for 32bit builds (deemed to be unnecessary)

- not yet release, but some of the API and file locations are closer
  to 1706 than to 1612. Needed, for example, for swak4foam.

- suppress error messages that appear with zsh.
  According to unset(1p), 'unset -f' unsets a function.
  If the function was not previously defined, this is a no-op.
  This is similar for zsh, but there it emits a warning if the
  function was not previously defined.

- avoid 'local' in functions sources from etc/bashrc.
  ksh does not support this.

- use 'command' shell builtin instead of 'type'.
  Seems to be more consistent between shell flavours.

- POSIX specifies '-c' for counting the number of matching lines,
  so we can just use that instead of 'wc' in wmake

- if called from the top-level project directory ($WM_PROJECT_DIR)
  default to using {applications,src} directories. This avoids
  erroneous linking of etc/codeTemplates and avoids the lengthy
  scanning of the tutorials directory

- minor bug: 'wclean empty' may have had issues with logical vs physical path

- handle sourcing bashrc with a relative path (issue #383)
- handle sourcing from bash and zsh.
  Still need manual intervention when sourcing dash, sh, or ksh.
- replace grep in etc/cshrc with sed only
- logical instead of physical path for WM_PROJECT_DIR (issue #431).
  Doesn't seem to be possible for csh/tcsh.

  * Continue using physical locations when comparing directories,
    but not for the top-level FOAM_INST_DIR, WM_PROJECT_DIR.

- relocate WM_CC, WM_CXX overrides from etc/config.*/compiler
  to etc/config.*/settings to ensure that they are left untouched
  when etc/config.sh/compiler is sourced while making third-party
  packages (eg, gcc, llvm, CGAL).

- provide fallback FOAM_TUTORIALS setting in RunFunctions

STYLE: remove "~OpenFOAM" fallback as being too rare, non-obvious

- minor cleanup of wmake sources

- easier to test or use different versions

- change WM_CXXFLAGS to -std=c++11 instead of -std=c++0x

- caused by the typo '@E' instead of '$E' (commit 997f1713)

ENH: minor improvements for wmake/src makefile

- 'make clean' now also tries to remove the parent platforms/
  directory if possible.

- the flex intermediate build target is placed into the platforms/
  directory to avoid touching the src/ directory at all.

- suppress warnings about unused functions (GCC only)

- makes it possible to filter out or highlight messages originating
  from wmkdep in the build process.

- new behaviour is to do nothing if no platform was specified.
  This helps avoid inadvertently removing files.

- support special platforms for compatibility with wmake/wclean targets.
  Eg, "wcleanPlatform all"

- allow use from ThirdParty top-level as well, since the directory
  structure is similar.

BUG: fix regression in wcleanLnIncludeAll introduced by 9e2e1115

STYLE: improve consistency in Allwclean scripts

- this may still need more testing, but the basic idea is to find
  directories with 'Allwclean' or 'Make' and process them (once!)

- use -name test before -type test to avoid calling stat(2) on every file.
- use -delete instead of -exec rm to avoid forking

- makes it slightly easier when packaging various binaries, or when
  building packages for installation via modules etc.

- reduces unexpected interactions between various make elements