Compiling Cbc@master with coinbrew@master fails

[kbrix2000]

Dear coinbrew developers,

currently compiling the master branch of Cbc with the master branch version of coinbrew following these instructions fails on a Debian GNU/Linux 11 system. There is an error while building Clp master using MPI, namely

[...]

##################################################
### Building Clp master
##################################################

Clp/src/ClpCholeskyMumps.cpp:22:10: fatal error: mpi.h: No such file or directory
   22 | #include "mpi.h"
      |          ^~~~~~~
compilation terminated.
make[2]: *** [Makefile:1017: ClpCholeskyMumps.lo] Error 1
make[1]: *** [Makefile:732: all] Error 2
make: *** [Makefile:459: all-recursive] Error 1

Error: Build failed, see error output above
$

In contrast, compiling older versions of Cbc, e.g. version 2.10.5 or 2.10.8, works fine using the master branch version of coinbrew.

Moreover, the old version 1.0 of coinbrew works well for the current master of Cbc besides the known incompatibility of MUMPS and a gcc newer than version 10, see e.g. #47 and the references therein (fix: add option ADD_FFLAGS=-fallow-argument-mismatch).

Could you please check? Thanks in advance!

[svigerske]

You may want to look in the log what version of ThirdParty-Mumps is build here.
ThirdParty-Mumps should define COIN_USE_MUMPS_MPI_H, either via the cflags in the coinmumps.pc or the mumps_compat.h that it builds. This should tell Clp to include mumps_mpi.h instead of mpi.h. Apparently that doesn't work.

The ADD_FFLAGS=-fallow-argument-mismatch should also not be necessary anymore. ThirdParty-Mumps should do this automatically, for years already.

[tkralphs]

The difference between coinbrew 1.0 and 2.0 is that coinbrew 1.0 gets the dependencies by parsing the .coin-or/Dependencies file, whereas in coinbrew 2.0, parsing .coin-or/config.yml became the default. While the actual dependencies are the same in both files, .coin-or/config.yml allows some dependencies to be listed as optional. Such dependencies are not built by default. Mumps is listed as optional. This should not cause a problem unless you happen to have first built with coinbrew 1.0 and then tried to re-build with 2.0 or something like that. Can you try from a fresh checkout or in a different build directory?

Alternatively if you add the flag --enable-optional, then 2.0 should behave in the same way as 1.0.