The MATLAB_CFLAGS variable was not injected when testing for the presence of
libslicot64_pic. In particular, on GNU/Linux system, this means that the -fPIC
flag was not injected when doing the test. This was not a problem on Debian,
where GCC now enables -fPIC by default. But this would fail on RHEL, where
-fPIC is not enabled by default.
By the way:
— rename ac_save_* variables to my_save_*, to avoid conflicts with internal
autoconf variables;
— do not inject “$(mkoctfile -p LFLAGS)” into LDFLAGS when testing for SLICOT
under Octave; this is no longer necessary, since those flags are already
injected at the beginning of mex/build/octave/configure.ac.
— allow the user to override compilation flags for MATLAB MEX (it was already
working for the preprocessor, the MEX for Octave and Dynare++)
— increase the symmetry of MEX build infrastructure between MATLAB and Octave
— when linking MEX for Octave, do not add the output of “mkoctfile -p FLIBS”.
It is unneeded, and it can create a conflict between the system compiler and
a user-supplied compiler
By the way:
— restore optimization on macOS for C/C++ MEX (it had been removed in
5df2392a09)
— remove -fno-omit-frame-pointer on MATLAB/Linux, since it would be cancelled
by subsequent -O2 and should not be needed anyways
— remove FFLAGS under Octave, unused