+# gl_COMMON
+# is expanded unconditionally through gnulib-tool magic.
+AC_DEFUN([gl_COMMON], [
+ dnl Use AC_REQUIRE here, so that the code is expanded once only.
+ AC_REQUIRE([gl_00GNULIB])
+ AC_REQUIRE([gl_COMMON_BODY])
+])
+AC_DEFUN([gl_COMMON_BODY], [
+ AH_VERBATIM([_Noreturn],
+[/* The _Noreturn keyword of C11. */
+#if ! (defined _Noreturn \
+ || (defined __STDC_VERSION__ && 201112 <= __STDC_VERSION__))
+# if (3 <= __GNUC__ || (__GNUC__ == 2 && 8 <= __GNUC_MINOR__) \
+ || 0x5110 <= __SUNPRO_C)
+# define _Noreturn __attribute__ ((__noreturn__))
+# elif defined _MSC_VER && 1200 <= _MSC_VER
+# define _Noreturn __declspec (noreturn)
+# else
+# define _Noreturn
+# endif
+#endif
+])
+ AH_VERBATIM([isoc99_inline],
+[/* Work around a bug in Apple GCC 4.0.1 build 5465: In C99 mode, it supports
+ the ISO C 99 semantics of 'extern inline' (unlike the GNU C semantics of
+ earlier versions), but does not display it by setting __GNUC_STDC_INLINE__.
+ __APPLE__ && __MACH__ test for Mac OS X.
+ __APPLE_CC__ tests for the Apple compiler and its version.
+ __STDC_VERSION__ tests for the C99 mode. */
+#if defined __APPLE__ && defined __MACH__ && __APPLE_CC__ >= 5465 && !defined __cplusplus && __STDC_VERSION__ >= 199901L && !defined __GNUC_STDC_INLINE__
+# define __GNUC_STDC_INLINE__ 1
+#endif])
+ AH_VERBATIM([unused_parameter],
+[/* Define as a marker that can be attached to declarations that might not
+ be used. This helps to reduce warnings, such as from
+ GCC -Wunused-parameter. */
+#if __GNUC__ >= 3 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 7)
+# define _GL_UNUSED __attribute__ ((__unused__))
+#else
+# define _GL_UNUSED
+#endif
+/* The name _UNUSED_PARAMETER_ is an earlier spelling, although the name
+ is a misnomer outside of parameter lists. */
+#define _UNUSED_PARAMETER_ _GL_UNUSED
+
+/* gcc supports the "unused" attribute on possibly unused labels, and
+ g++ has since version 4.5. Note to support C++ as well as C,
+ _GL_UNUSED_LABEL should be used with a trailing ; */
+#if !defined __cplusplus || __GNUC__ > 4 \
+ || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5)
+# define _GL_UNUSED_LABEL _GL_UNUSED
+#else
+# define _GL_UNUSED_LABEL
+#endif
+
+/* The __pure__ attribute was added in gcc 2.96. */
+#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
+# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
+#else
+# define _GL_ATTRIBUTE_PURE /* empty */
+#endif
+
+/* The __const__ attribute was added in gcc 2.95. */
+#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95)
+# define _GL_ATTRIBUTE_CONST __attribute__ ((__const__))
+#else
+# define _GL_ATTRIBUTE_CONST /* empty */
+#endif
+])
+ dnl Preparation for running test programs:
+ dnl Tell glibc to write diagnostics from -D_FORTIFY_SOURCE=2 to stderr, not
+ dnl to /dev/tty, so they can be redirected to log files. Such diagnostics
+ dnl arise e.g., in the macros gl_PRINTF_DIRECTIVE_N, gl_SNPRINTF_DIRECTIVE_N.
+ LIBC_FATAL_STDERR_=1
+ export LIBC_FATAL_STDERR_
+])
+
+# gl_MODULE_INDICATOR_CONDITION
+# expands to a C preprocessor expression that evaluates to 1 or 0, depending
+# whether a gnulib module that has been requested shall be considered present
+# or not.
+m4_define([gl_MODULE_INDICATOR_CONDITION], [1])
+
+# gl_MODULE_INDICATOR_SET_VARIABLE([modulename])
+# sets the shell variable that indicates the presence of the given module to
+# a C preprocessor expression that will evaluate to 1.
+AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE],
+[
+ gl_MODULE_INDICATOR_SET_VARIABLE_AUX(
+ [GNULIB_[]m4_translit([[$1]],
+ [abcdefghijklmnopqrstuvwxyz./-],
+ [ABCDEFGHIJKLMNOPQRSTUVWXYZ___])],
+ [gl_MODULE_INDICATOR_CONDITION])
+])
+
+# gl_MODULE_INDICATOR_SET_VARIABLE_AUX([variable])
+# modifies the shell variable to include the gl_MODULE_INDICATOR_CONDITION.
+# The shell variable's value is a C preprocessor expression that evaluates
+# to 0 or 1.
+AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX],
+[
+ m4_if(m4_defn([gl_MODULE_INDICATOR_CONDITION]), [1],
+ [
+ dnl Simplify the expression VALUE || 1 to 1.
+ $1=1
+ ],
+ [gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([$1],
+ [gl_MODULE_INDICATOR_CONDITION])])
+])
+
+# gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR([variable], [condition])
+# modifies the shell variable to include the given condition. The shell
+# variable's value is a C preprocessor expression that evaluates to 0 or 1.
+AC_DEFUN([gl_MODULE_INDICATOR_SET_VARIABLE_AUX_OR],
+[
+ dnl Simplify the expression 1 || CONDITION to 1.
+ if test "$[]$1" != 1; then
+ dnl Simplify the expression 0 || CONDITION to CONDITION.
+ if test "$[]$1" = 0; then
+ $1=$2
+ else
+ $1="($[]$1 || $2)"
+ fi
+ fi
+])
+