NAME

       dcl2inc - postprocess ftnchek .dcl files to create separate INCLUDE files

SYNOPSIS

       dcl2inc *.dcl

DESCRIPTION

       dcl2inc  postprocessing declaration files output by ftnchek(1), replacing unique COMMON block definitions
       by Fortran INCLUDE statements.  For each input .dcl file,  a  modified  output  .dcn  file  is  produced,
       together with include files named by the COMMON block name, with filename extension .inc.

       In  addition,  dcl2inc  produces  on stdout a list of Makefile dependencies for the UNIX make(1) utility.
       These can be appended to the project Makefile to ensure that any subsequent changes to .inc files provoke
       recompilation of source files that include them.

       dcl2inc  warns  about  COMMONs  which  differ  from their first occurrence, and simply copies them to the
       output .dcn file, instead of replacing them with an INCLUDE statement.  Thus, any COMMON statements  that
       are  found  in  the output .dcn files should be examined carefully to determine why they differ: they may
       well be in error.

       Replication of identical data, and bugs arising from subsequent modification of only part  of  it,  is  a
       significant  reason  why  Fortran  programming  projects should require that COMMON declarations occur in
       separate include files, so that there is only a single point of definition of any global object.

       Even though the Fortran INCLUDE statement was tragically omitted from the 1977 Standard, it has long been
       implemented  by  virtually all compiler vendors, and is part of the 1990 Standard.  In practice, there is
       therefore no portability problem associated with use of INCLUDE  statements,  provided  that  one  avoids
       nonportable  file  names.  As long as the code obeys Fortran's limit of six-character alphanumeric names,
       the filenames generated by dcl2inc will be acceptable on all current popular operating systems.

       Fortran's default, or IMPLICIT, variable typing is deprecated in modern programming languages, because it
       encourages sloppy documentation, and worse, bugs due to misspelled variables, or variables that have been
       truncated because they extend past column 72.  If all variables used are explicitly typed, and a compiler
       option  is  used  to  reject  all  program units with untyped variables, variable spelling and truncation
       errors can be eliminated.

       Variable declarations that have been produced automatically by a tool like ftnchek(1) or pfort(1) have  a
       consistent  format  that  facilitates  application  of stream editors (e.g. to change array dimensions or
       rename variables), and simple floating-point precision conversion tools like  d2s(1),  dtoq(1),  dtos(1),
       qtod(1), s2d(1), and stod(1).

CAVEAT

       The current version (2.9) of ftnchek(1) does not produce Fortran EQUIVALENCE statements in .dcl files, so
       you must be careful to preserve them when replacing original declarations with new ones from .dcl or .dcn
       files.

SEE ALSO

       d2s(1), dtoq(1), dtos(1), ftnchek(1), make(1), pfort(1), qtod(1), s2d(1), stod(1).

AUTHOR

       Nelson H. F. Beebe, Ph.D.
       Center for Scientific Computing
       Department of Mathematics
       University of Utah
       Salt Lake City, UT 84112
       Tel: +1 801 581 5254
       FAX: +1 801 581 4148
       Email: <beebe@math.utah.edu>