# We need to be careful to avoid having the reference to # program_invocation_name optimized out. We do that by # returning the value. AC_DEFUN([AC_PROGRAM_INVOCATION_NAME], [AC_CACHE_CHECK( for program_invocation_name, ac_cv_have_program_invocation_name, AC_LINK_IFELSE([AC_LANG_PROGRAM([[extern char* program_invocation_name;]], [[return *program_invocation_name;]])],[ac_cv_have_program_invocation_name=yes],[ac_cv_have_program_invocation_name=no]) ) if test "$ac_cv_have_program_invocation_name" = "yes"; then AC_DEFINE(HAVE_PROGRAM_INVOCATION_NAME, 1, [define if libc has program_invocation_name]) fi ])