Download M4 Source Macro History Category Index

_ac_c_ifdef

Synopsis

_AC_C_IFDEF(MACRO-NAME, ACTION-IF-DEF, ACTION-IF-NOT-DEF)

Description

Check for the definition of macro MACRO-NAME using the current language's compiler.

Author

Ludovic Courtès <ludo@chbouib.org>

Last Modified

2004-09-07

Cross References

group0-xrefs.png

M4 Source Code 

AC_DEFUN([_AC_C_IFDEF],
  [AC_COMPILE_IFELSE([#ifndef $1
                      # error "Macro $1 is undefined!"
                      /* For some compilers (eg. SGI's CC), #error is not
                         enough...  */
                      please, do fail
                      #endif],
                     [$2], [$3])])

License

Copyright © 2004 Ludovic Courtès <ludo@chbouib.org>

Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved.