- The -Wno-deprecated-copy flag for gcc-9.2.0
In the future we may indeed wish to explicitly request default
generated constructors and assignment operators, but at the moment
these are still acceptable.
- The -Wno-alloc-size-larger-than flag for mingw compilations
Related to differences in PTRDIFF_MAX vs SIZE_MAX on the target.
Several issues related to this can be found in the gcc bug reports
and on stackoverflow etc.
Set the m4 -I include accordingly to have the folllowing:
- the directory of the parser.
- include/ in the top-level source tree of the current target
(eg, src/finiteVolume/include-m4/ when compiling libfiniteVolume)
- include/ from OpenFOAM
Additional -dry-run option for makeParser, wrap-lemon for expanding m4
only.
Extend m4 wrapping support to include bison as well.
- add additional rule (ending '.ll') for the combination of
flex for C-code but compiling the result as C++.
This can be needed for re-entrant parsers.
- update bison rule to handle renaming of skeleton files.
Use a wrap-bison script to manage this.
- with 1906, OpenFOAM is purely C++ code and the last toolchain bits C
code have been avoided. Thus relax the wmake C rule for including
WM_COMPILE_OPTION. This makes it much easier to add different
compiler options with fewer files.
For example, for Broadwell-specific options:
cd wmake/rules/linux64Gcc
cp c++Opt c++OptBdw
edit this file and then use WM_COMPILE_OPTION=OptBdw
- ensure that WM_COMPILE_OPTION is always non-empty
- When building OpenFOAM for different platform combinations
(single/double, int32/int64) the build information that is compiled
into the OpenFOAM lib can become out of sync.
This is because the update trigger (wmakeBuildInfo -check) is
independent of the targetted platform. The added file
'src/OpenFOAM/Alltouch' provides a direct means of forcing a rebuild
of the version information. Eg,
src/OpenFOAM/Alltouch
wmake src/OpenFOAM
Also provide an additional 'wmakeBuildInfo -remove' to forcibly
remove META-INFO/build-info, if that is desired.
- now only needed when specify compiling -m32 on a 64-bit system.
Internally use the __SIZEOF_LONG__ compiler macro (gcc, icc, llvm)
to define when long is actually an int32_t.
- remove make target for wmdep (flex-based scanner), which eliminates
a bootstrap dependency on flex.
As of OpenFOAM-v1806, wmdep has been superseded by wmdepend
(ragel-based scanner).
- replace dirToString binary with shell/awk equivalent for simpler
maintenance. The utility is very rarely used (auto scanning to
create Make/files) so there is no performance difference.
- forces c++DBUG='-DFULLDEBUG -g -O0' for the compilation, to allow
localized debugging during development without file editing and
while retaining the WM_COMPILE_OPTION (eg, Opt)
Note that switching between 'wmake' and 'wmake -debug' will not
cause existing targets to be rebuilt. As before, these are driven by
the dependencies. An intermediate wclean may thus be required.
- when windows portable executables (.exe or .dll) files are loaded,
their dependent libraries not fully loaded. For OpenFOAM this means
that the static constructors which are responsible for populating
run-time selection tables are not triggered, and most of the run-time
selectable models will simply not be available.
Possible Solution
=================
Avoid this problem by defining an additional library symbol such as
the following:
extern "C" void libName_Load() {}
in the respective library, and tag this symbol as 'unresolved' for
the linker so that it will attempt to resolve it at run-time by
loading the known libraries until it finds it. The link line would
resemble the following:
-L/some/path -llibName -ulibName_Load
Pros:
- Allows precise control of forced library loading
Cons:
- Moderately verbose adjustment of some source files (even with macro
wrapping for the declaration).
- Adjustment of numerous Make/options files and somewhat ad hoc
in nature.
- Requires additional care when implementing future libraries and/or
applications.
- This is the solution taken by the symscape patches (Richard Smith)
Possible Solution
=================
Avoid this problem by simply force loading all linked libraries.
This is done by "scraping" the information out of the respective
Make/options file (after pre-processing) and using that to define
the library list that will be passed to Foam::dlOpen() at run-time.
Pros:
- One-time (very) minimal adjustment of the sources and wmake toolchain
- Automatically applies to future applications
Cons:
- Possibly larger memory footprint of application (since all dependent
libraries are loaded).
- Possible impact on startup time (while loading libraries)
- More sensitive to build failures. Since the options files are
read and modified based on the existence of the dependent
libraries as a preprocessor step, if the libraries are initially
unavailable for the first attempt at building the application,
the dependencies will be inaccurate for later (successful) builds.
- This is solution taken by the bluecape patches (Bruno Santos)
Adopted Solution
================
The approach taken by Bruno was adopted in a modified form since
this appears to be the most easily maintained.
Additional Notes
================
It is always possible to solve this problem by defining a corresponding
'libs (...)' entry in the case system/controlDict, which forces a dlOpen
of the listed libraries. This is obviously less than ideal for large-scale
changes, but can work to resolve an individual problem.
The peldd utility (https://github.com/gsauthof/pe-util), which is
also packaged as part of MXE could provide yet another alternative.
Like ldd it can be used to determine the library dependencies of
binaries or libraries. This information could be used to define an
additional load layer for Windows.
- 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)
- 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.
