Known issues when building SIESTA¶

SIESTA does not recognize the compiler I want to use¶

Different environments might result in SIESTA not detecting automatically your compiler and defaulting to the GNU compiler, getting the following message:

-- The Fortran compiler identification is GNU 9.4.0
-- The C compiler identification is GNU 9.4.0

If your intention was to use other compilers, such as Intel or Cray, you can override the compiler in cmake using the CC, FC and MPIFC environment variables at the configuration step. For example:

CC=icc FC=ifort MPIFC=mpiifort cmake -S. -B _build ...[Your Options Here]...

In this case, this will force cmake to use the Intel compiler (if available).

SIESTA does not recognize GNU ScaLAPACK¶

In some Linux-native versions of the ScaLAPACK distribution, CMake detection might fail with the following message:

CMake Warning at CMakeLists.txt:63 (message):
MPI is found, but ScaLAPACK library cannot be found (or compiled against).
If parallel support is required please supply the ScaLAPACK library with
appropriate flags:
-DSCALAPACK_LIBRARY=<lib>

In order to fix this, the cmake variable -DSCALAPACK_LIBRARY must be explicitly set to -DSCALAPACK_LIBRARY="-lscalapack-openmpi" (or the appropriate ScaLAPACK version in your system):

cmake -S. -B _build ...[Your Options Here]... -DSCALAPACK_LIBRARY="-lscalapack-openmpi"

SIESTA does not recognize Intel MKL libraries¶

When using Intel-provided compilers and libraries (such as OneAPI), you might need to set the name for linear algebra libraries manually:

cmake -S. -B _build ...[Your Options Here]... \
-DLAPACK_LIBRARY="-lmkl_intel_lp64 -lmkl_sequential -lmkl_core" \
-DSCALAPACK_LIBRARY="-lmkl_scalapack_lp64 -lmkl_blacs_intelmpi_lp64 -lmkl_intel_lp64 -lmkl_sequential -lmkl_core"

Issues with Cray compilers¶

There are few known issues when compiling SIESTA with Cray compilers.

Compilation with debug information “-g” fails for Cray Compiler versions lower than 14.0.3.
For Cray versions 15.0 or higher available on certain systems, it might be mandatory to manually add a compiler flag for OpenMP compilations. For example:
```
cmake -S. -B _build ...[Your Options Here]... -DFortran_FLAGS="-fopenmp"
```

Missing readline (FLOOK)¶

CMake configuration may fail with an error similar to this one:

CMake Error at External/Lua-Engine/CMakeLists.txt:49 (find_library):
  Could not find _flook_lib_readline using the following names: readline
Call Stack (most recent call first):
  External/Lua-Engine/CMakeLists.txt:229 (flook_add_dependencies)

This happens when you are missing the readline package in your system. You can either disable FLOOK for your compilation if you don’t need it (-DWITH_FLOOK=off), or install readline. In modern Debian-based distributions such as Ubuntu this is as easy as:

apt install readline-common