The change from C++0x to C++11 allows all of C++11 functionality to be
used in OpenFOAM, in particular constructor delegation which avoids code
duplication or constructor helper functions. However, this also means a
change to the minimum gcc version supported which is now 4.7 rather than
4.5.
Note that gcc-4.7 does not support the entire C++11 standard but does
support all of the functionality currently needed for further OpenFOAM
development. The minimum gcc-version which supports the entire C++11
standard is 4.8 which is now the recommended minimum gcc version.
1. "foamCompiler" was changed to a more permanent "WM_COMPILER_TYPE"
environment variable, so that it can be used by 3rd party
installation scripts, such as "makeGcc", "makeLLVM" and so on. More
on this will be provided in issue #1215.
2. The script functions such as "_foamSource()" and "_foamAddPath()"
were moved to a new file "etc/config.sh/functions". It has the
ability to set or unset, depending on whether "WM_BASH_FUNCTIONS" is
defined or not. This allows for these functions to be reused by
other scripts, such as "makeGcc".
3. The script "etc/config.sh/CGAL" relies on whether a local
environment variable "SOURCE_CGAL_VERSIONS_ONLY" is defined or not,
so that it will load only the version settings if it's defined. This
is to make it easier to call this script from "makeCGAL". Although
it still feels a bit of a clunky hack, but I didn't manage to deduce
any other way we could do this :( I didn't add indentation within
the if-block, to make it easier to read the changes. In addition,
the local variable "common_path" is used to shorten the length of
the lines and use slightly less repeated code.
4. Added another new script "etc/config.sh/compiler", which has only
the version numbers for the compilers taken out from the "settings"
file. It currently depends on "WM_COMPILER_TYPE" for setting the
variables, the same way it did with "foamCompiler". This script is
now always sourced from the "settings" file, for the following
reasons:
- "makeGCC" and "makeLLVM" can now take advantage of this script file.
- The example "compiler" script (detailed next) can rely on this
script file and then override parameters on-demand, as well as
allowing for system compilers to have dedicated settings, such as
setting "WM_CC". This is similar to how the example environment
script for "paraview" works.
5. To the script "etc/config.sh/example/compiler" were added a few more examples:
- It now starts with a block where it first loads the default "compiler" script.
- Has a "WM_COMPILER=Gcc48u" case example for when we try to use GCC
4.8 in Ubuntu 15.10. This is just to give the idea that in a
particular system, we might have several system-wide compiler
versions. For example, in Ubuntu 15.10, there is GCC 4.7, 4.8 and
5.2, which could be used for testing performances or compatibility
with some other 3rd party library.
- Has the "WM_COMPILER=Icc" case example, related to the original bug
report, where "WM_CC=icc" and "WM_CXX=icpc", so that the user then
simply copies this file to their own local preferences folder.
6. Small bug fix in "etc/config.sh/mpi", where unsetting "minBufferSize" was missing at the end of the script.
7. Small change in "etc/config.sh/paraview", where "CMAKE_ROOT" is set
along with "CMAKE_HOME". This is due to a rare issue that occurs on
people's systems where they have a custom system-wide CMake version
installed and which is used by having "CMAKE_ROOT" set on that
environment. This can mess up OpenFOAM's custom ParaView builds,
given that conflicting CMake versions can lead to not building
ParaView at all.
- For more details about "CMAKE_ROOT":
https://cmake.org/Wiki/CMake_Useful_Variables [^]
8. The scripts "_foamAddPath _foamAddLib _foamAddMan" were not being
unset at the end of "settings". They are now unset at the end of
"bashrc", through a call to the new double-use "functions" script.
Additionally all references to "foamCompiler" have been changed to
"WM_COMPILER_TYPE".
See also http://www.openfoam.org/mantisbt/view.php?id=1232
