arch-linux-howto.md

+# How to compile on Arch Linux
+
+## Packages
+We need to install some packages, from the regular repositories and from AUR
+
+We need the following packages : 
+* openmpi
+* cmake
+* mumps (version 5, from AUR)
+* Scalapack ( version >= 2, from AUR)
+* Superlu (version 4, from AUR)
+* parmetis
+* metis4 (from AUR)
+* openblas (from AUR)
+
+## Compile Taucs
+Unfortunately, we need to compile Taucs (which is not maintained anymore). We can follow the installation README from softserver.
+
+The associated config file is attached: [linux_Arch.mk](/uploads/7164ec3bb9c95d5da4bf6e5031788252/linux_Arch.mk)
+
+In order to work with gcc >= 6, `src/taucs.h` must be modified. You must comment `extern int isnan(double);` and `extern int isinf(double);`
+
+Everything is installed into `$(DEVROOT)/myLibs/TAUCS_2.2`.
+
+##  Superlu
+Installed from AUR (**version 4 !!!**)
+
+Then, you must modify `xLinearSystemSolverSuperLu.cc` and chose `#define SUPERLU_VERSION 4`
+
+**Attention:** The only supported version is version 3. Version 4 works (except the conditioning number estimation), but this is experimental
+
+## CMakeLists.txt
+My `CmakeLists.txt` is in `GEMUtil`. Basically,  only the next lines differ from the default options:
+
+```cmake
+option(MUMPSV5 "use mumps version 5 or above (scotch/metis new API integration)" ON)
+
+###############
+# sclalapack version 
+# with version 2 and above scalapack integrate blacs
+option(SCALAPACKV2 "Use scalapack version 2 or above" ON)
+###############
+
+
+SET(ENV{TAUCSLIB} "${DEVROOT}/myLibs/TAUCS_2.2/lib/linux_Arch/libtaucs.a")
+SET(ENV{TAUCSINC} "${DEVROOT}/myLibs/TAUCS_2.2/src")
+SET(ENV{TAUCSCONFIG} "${DEVROOT}/myLibs/TAUCS_2.2/build/linux_Arch")
+SET(ENV{TAUCSTESTINC} "${DEVROOT}/myLibs/TAUCS_2.2/build/linux_Arch")
+
+SET(ENV{SUPERLUINC} "/usr/include/superlu")
+SET(ENV{MPIHOME} "/usr/bin")
+```
+
+And that's all...