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generated...
2007-08-05

(C) 2007 guidod
Download the M4 Source.

_ac_c_ifdef

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

2004-09-07

Author

Ludovic Court├Ęs <ludo@chbouib.org>

License

AllPermissive
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. Users of this software should generally follow the principles of the MIT License includings its disclaimer.

Category

cryp.to ac-archive's Miscellaneous (released)

Documentation

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

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])])