"Error Unclassifiable statement" on Linux [duplicate] - linux

Question

This question already has an answer here:
Error: Non-numeric character in statement label at (1)?
(1 answer)
Closed 6 years ago.
Compile .for format file using gfortran in my Linux cluster.
By typing gfortran -O2 calpuff.for -o calpuff.exe, there happened to be one error:
Unclassifiable statement
Error
In file calutils.for:2912
Included at calpuff.for:2115
cdeflt=ctext
Error: Unclassifiable statement at (1)
Corresponing calutil.for shows like:
c ----------------------------------------
c
character*132 ctext,cdeflt
c
c --- Microsoft variables
c *** integer*2 iarg,istat
c
c --- HP declaration
c *** external getarg
c *** external iargc
c
c --- The following is for any system without a command line routine
c --- and is also used as a default
cdeflt=ctext ## Line 2912
c
c ----------------------------------------
c ----------------
## Another subroutine.
c --- Sun compiler
c ----------------
numargs=IARGC()
if(numargs.ge.1)then
call GETARG(1,ctext)
endif
### Add another subroutine which are the only code related to `cdeflt`
c --- If no command line arguments, use default
if(ctext(1:1).eq.' ')ctext=cdeflt # Line 2954
return
end
Update
Thanks for #Alexander Vogt's remind, the code below is calpuff.for.
c----------------------------------------------------------------------
c --- BRING IN SUBROUTINES for MCHEM=6,7 OPTIONS (API)
include 'api_chem.for'
include 'isorropia.for'
c --- BRING IN CALPUFF SYSTEM UTILITY SUBROUTINES
include 'calutils.for' ###　This is line 2115
include 'coordlib.for'
c----------------------------------------------------------------------
What's wrong with cdeflt=ctext? Can someone give some advice?

Answer 1

The actual error occurs in the lines afterwards:
c ----------------
c --- Sun compiler
c ----------------
numargs=IARGC()
if(numargs.ge.1)then
call GETARG(1,ctext)
endif
You just have five blanks in there, (at least) six are required. It should read
c ----------------
c --- Sun compiler
c ----------------
numargs=IARGC()
if(numargs.ge.1)then
call GETARG(1,ctext)
endif
In fixed form Fortran, the first six columns have a special meaning and may not be used for code.
Unfortunately, this (again) makes your question a duplicate of a multitude of others on SO.