_ac_c_ifdef

Download the M4 Source.

Synopsis

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

Version

20040907 0.5.65 : Miscellaneous

Author

Ludovic Courtès <ludo@chbouib.org>

Description

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])])