AC_DEFUN([AC_PROG_CC_PIE], [
	AC_CACHE_CHECK([whether ${CC-cc} accepts -fPIE], ac_cv_prog_cc_pie, [
		echo 'void f(){}' > conftest.c
		if test -z "`${CC-cc} -fPIE -pie -c conftest.c 2>&1`"; then
			ac_cv_prog_cc_pie=yes
		else
			ac_cv_prog_cc_pie=no
		fi
		rm -rf conftest*
	])
])

AC_DEFUN([AC_PATH_READLINE], [
	AC_CHECK_HEADER(readline/readline.h,
		[AC_CHECK_LIB(readline, main,
			[ readline_found=yes
			AC_SUBST(READLINE_LIBS, "-lreadline")
			], readline_found=no)],
		[])
])

AC_DEFUN([COMPILER_FLAGS], [
	if (test "${CFLAGS}" = ""); then
		CFLAGS="-Wall -O2 -D_FORTIFY_SOURCE=2"
	fi
	if (test "$USE_MAINTAINER_MODE" = "yes"); then
		CFLAGS="$CFLAGS -Werror -Wextra"
		CFLAGS="$CFLAGS -Wno-unused-parameter"
		CFLAGS="$CFLAGS -Wno-missing-field-initializers"
		CFLAGS="$CFLAGS -Wdeclaration-after-statement"
		CFLAGS="$CFLAGS -Wmissing-declarations"
		CFLAGS="$CFLAGS -Wredundant-decls"
		CFLAGS="$CFLAGS -Wcast-align"
		CFLAGS="$CFLAGS -DG_DISABLE_DEPRECATED"
	fi
])