Supported Compilers

Selecting a compiler

Use the --compiler flag (case-insensitive, tab-completable):

fobis build --compiler gnu
fobis build --compiler intel
fobis build --compiler custom --fc g95 --modsw "-fmod="

Or set it in the fobos file:

[default]
compiler = gnu

Built-in compilers

Identifier	Compiler
gnu	GNU gfortran
intel	Intel Fortran Compiler Classic (ifort)
intel_nextgen	Intel Fortran Compiler (ifx)
g95	g95
opencoarrays-gnu	OpenCoarrays + gfortran
pgi	PGI Fortran Compiler
ibm	IBM XL Fortran
nag	NAG Fortran Compiler
nvfortran	NVIDIA HPC Fortran (nvfortran)
amd	AMD Flang (amdflang)
custom	User-defined — requires --fc and optionally --modsw

Custom compiler

For any compiler not listed, use custom and specify the executable and module path switch:

fobis build --compiler custom --fc /opt/myfc/bin/myfc --modsw "-module "

In a fobos file:

[default]
compiler = custom
fc       = /opt/myfc/bin/myfc
modsw    = -module
cflags   = -c -O2

Compiler variants

MPI

Enable the MPI-wrapped compiler variant:

fobis build --mpi

This switches to the MPI wrapper (e.g. mpif90 for GNU, mpiifort for Intel).

OpenMP

fobis build --openmp

Adds the appropriate OpenMP flag for the selected compiler.

OpenMP offloading

fobis build --openmp-offload

Coarrays

fobis build --coarray

Coverage instrumentation

Instrument the build for gcov-compatible coverage analysis:

fobis build --coverage

After running the program, analyze .gcov files with the intrinsic rule:

fobis rule --gcov-analyzer reports/ summary

Profiling

fobis build --profile

Compilation and linking flags

Override the default flags for the selected compiler:

fobis build --cflags " -c -O3 -march=native" --lflags " -O3"

Or in fobos:

[default]
cflags = -c -O3 -march=native
lflags = -O3

Flag prefixing

Prepend a space to flag strings to avoid the parser misinterpreting flags that start with -. See the Quick Start note.

Preprocessor flags

Pass flags to the compiler's built-in preprocessor (e.g. -D macros):

fobis build --preproc " -DDEBUG -DUSE_MPI"

In fobos:

[default]
preproc = -DDEBUG -DUSE_MPI