Supported Preprocessor Directives

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Supported preprocessor directive list

• #include : Header file inclusion
• #define : Macro expansion
• #error : Preprocessor error report
• #ifdef : Conditional compilation based on macro with definitions
• #ifndef : Conditional compilation based on macro without definitions
• #if : Conditional compilation based on conditional expressions
• #elif : Conditional compilation based on conditional expressions
• #else : Conditional compilation based on conditional expressions
• #endif : End mark of conditional compilation area.

A FORTRAN example

• File1: macros.h

  #ifdef ERR
  #error 'ERR is defined.'
  #endif
  #define MSG_HW "Hello World!"
  #define MSG_HI "Hi, "
  #define MSG_BW "Bye World!"
  #define MSG_NM ".."
  #ifndef NAME
  #define NAME "FORTRAN"
  #endif
  

• File2: preproc.f

  #include "macros.h"
  
  C      A Fortran program example used for testing that
  C      ABC shall correctly handle C preprocessor directives
  C      defined in Fortran source code.
  C      Directives are used mainly for two purposes:
  C        1. User-specified conditional compilation
  C        2. Macro expansion / String substitution
  C      Directives tested here are: 
  C        "include", "define", "undef", "if", "ifdef", "ifndef"
  C        "error"
  
         program HelloWorld
  #if NUM_MSG==1
            print *, MSG_HW
  #elif NUM_MSG==2
            print *, MSG_HW
            print *, MSG_HI, NAME
  #elif NUM_MSG>=3
            print *, MSG_HW
            print *, MSG_HI, NAME
  #ifdef BYE
            print *, MSG_BW
  #undef BYE
  #endif
  #ifdef BYE
  #error "BYE should be undefined." 
  #endif
  #else
            print *, MSG_NM
  #endif
         end