Fortran: check for undeclared variables by forcing implicit none everywhere
C/C++: check for unused parameters and return types
removed unused variables from test cases
ci: do missing return and unused arg check with Github Actions
* intel-cl tests: more rigorous detection of intent to use Intel Windows compilers
* fortran coarray test: make skipping more robust in that underlying MPI stack is .run()
This is useful for any Fortran coarray work, and especially for intel-cl where multiple Intel compiler
versions are often installed, and the wrong underlying MPI library may be dynamically linked,
and so a runtime check is needed to exercise the MPI stack underlying Fortran coarray.
This is done by
fc.run('sync all; end', dependencies: coarray)
* pep8
Apparently we have no tests for this because this is broken pretty
badly. This extends the basic test to actually check for the correct
free-form argument and thus test this.
This test currently assumes that the fortran compiler is gfotran, and
if we're not using g++ it skips. This patch changes it to skip if the
fotran compiler and the c++ compiler aren't the same family. This still
may skip in some cases it shouldn't (clang and gfort probably work fine
on windows), but it does enable ifort + ICL. Which is hte point.
* mesonbuild/compilers/c.py: Make the `find_library` method more generic by allowing the user to supply the `code` for compiling and linking.
* mesonbuild/compilers/fortran.py: Use the methods inherited from `Compiler` base class where appropriate. Also reuse `CComiler` methods where applicable. This should be sufficient to get various compiler/linker arguments as well as to compile and link Fortran programs. This was tested with `gfortran` compiler, and while the other compilers ought to work for simple cases, their methods are primarily inherited from the base `FortranCompiler` class.
* test cases/fortran/10 find library/gzip.f90: Fortran module with some basic Fortran wrapper interfaces to `gzopen`, `gzwrite`, and `gzclose` C `zlib` functions.
* test cases/fortran/10 find library/main.f90: Fortran program using the `gzip` Fortran interface module to write some data to a gzip file.
* test cases/fortran/10 find library/meson.build: Meson build file for this test case. This demonstrates the ability to link the Fortran program against an external library.