single precision reading does not handle 1e-39 or lower
in v1706 this does work - it underflows and truncates to 0.
This is used when generating meshes in double precision but then running with single precision.
Replicate: change on e.g. cavity one of the points in constant/polyMesh/points to
(0.01 1e-39 0)
and run e.g. checkMesh. Will produce error
--> FOAM FATAL IO ERROR: Attempt to get back from bad stream file: /home/preston2/mattijs/OpenFOAM/OpenFOAM-plus.develop/tutorials/incompressible/icoFoam/cavity/cavity/constant/polyMesh/points at line 23. From function bool Foam::Istream::getBack(Foam::token&) in file db/IOstreams/IOstreams/Istream.C at line 56. FOAM aborting (FOAM_ABORT set)