setExprFields floatingPointException evaluating log of variable

Summary

When using an expressing in setExprFields containing log of a variable it exits with a floating point exception.

Steps to reproduce

Run setExprFields using a an expression that contains log(variable)

Example case

Modify tutorials/compressible/rhoPimpleFoam/RAS/TJunctionAverage/system/setExprFieldsDict so that the expression is:

        expression
        #{
            300
          + log(radius)
        #};

Additionally this also doesn't work:

        expression
        #{
            300
          + log(10*radius)
        #};

However this works correctly:

        expression
        #{
            300
          + log(1/radius)
        #};

What is the current bug behaviour?

Exits with a floating point exception when a strange set of criteria is met.

What is the expected correct behavior?

The variable is evaluated correctly and the correct field values are applied.

Relevant logs and/or images

/*---------------------------------------------------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  2006                                  |
|   \\  /    A nd           | Website:  www.openfoam.com                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
Build  : _295eef47-20201012 OPENFOAM=2006 patch=201012
Arch   : "LSB;label=32;scalar=64"
Exec   : setExprFields
Date   : Oct 21 2020
Time   : 10:01:35
Host   : chimera
PID    : 18880
I/O    : uncollated
Case   : /****/TJunctionAverage
nProcs : 1
trapFpe: Floating point exception trapping enabled (FOAM_SIGFPE).
fileModificationChecking : Monitoring run-time modified files using timeStampMaster (fileModificationSkew 5, maxFileModificationPolls 20)
allowSystemOperations : Allowing user-supplied system call operations

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time

Create mesh for time = 0


Time = 0
Modify field: T (type volScalarField) time=0
Expression:
>>>>

            300
          + log(10*radius)
        
<<<<
Condition:
>>>>

            (mag(pos() - vector(0.21,0,0.01)) < radius)

          && pos((pos() - vector(0.21,0,0.01)).y()) > 0
        
<<<<

#0  Foam::error::printStack(Foam::Ostream&) at ??:?
#1  Foam::sigFpe::sigHandler(int) at ??:?
#2  ? in /lib64/libpthread.so.0
#3  log in /lib64/libm.so.6
#4  Foam::log(Foam::Field<double>&, Foam::UList<double> const&) at ??:?
#5  Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > Foam::log<Foam::fvPatchField, Foam::volMesh>(Foam::tmp<Foam::GeometricField<double, Foam::fvPatchField, Foam::volMesh> > const&) at ??:?
#6  ? at volumeExprLemonParser.cc:?
#7  Foam::expressions::volumeExpr::parser::parse(int, Foam::expressions::volumeExpr::scanToken*) at ??:?
#8  Foam::expressions::volumeExpr::scanner::process(std::string const&, unsigned long, unsigned long, Foam::expressions::volumeExpr::parseDriver&) at ??:?
#9  Foam::expressions::volumeExpr::parseDriver::parse(std::string const&, unsigned long, unsigned long) at ??:?
#10  ? at ??:?
#11  ? at ??:?
#12  __libc_start_main in /lib64/libc.so.6
#13  ? at ??:?
Floating point exception (core dumped)

Environment information

• OpenFOAM version : v2006
• Operating system : centoOS 7
• Hardware info : Intel E5-1620, 64GB RAM
• Compiler : gcc 4.8.5

OpenFOAM installed using the yum package manager as described in the release notes.

Possible fixes