Following the build guide page with v1606+ on Ubuntu 16.04 will fail with foamDebugSwitches

Following the instructions at http://openfoam.com/code/build-guide.php will result in not having a complete build, when building on Ubuntu, because dash is the default sh.

This is already fixed in the Development/ThirdParty-plus/#2 (closed), but the ThirdParty-v1606+ tarball package still has a bug that will not allow building the FFTW library.

And due to that bug, the foamDebugSwitches utility will not build due to the dependency on the randomProcesses library, which will in turn block the remaining run of make, unless the -k option is used in the call to the main Allwmake.

Short term fix

The user-side fix is to run the following commands, before running Allwmake (as documented here):

cd $WM_THIRD_PARTY_DIR
 
sed -i -e 's=unset _foamAddPath=unset -f _foamAddPath=' makeFFTW

cd $WM_PROJECT_DIR

Long term fix

Reminder: foamDebugSwitches was deprecated in the OpenFOAM Foundation repositories, in favour of a general foamList.
Add a Allwmake script which sets optional library dependencies, as done in $FOAM_UTILITIES/surface/surfaceBooleanFeatures/Allwmake and update Make/options accordingly.