-# timer_time.m4 serial 2
-dnl Copyright (C) 2011-2013 Free Software Foundation, Inc.
+# timer_time.m4 serial 3
+dnl Copyright (C) 2011-2014 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
dnl Based on clock_time.m4. See details there.
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
- AC_REQUIRE([gl_THREADLIB])
+
+ dnl Test whether the gnulib module 'threadlib' is in use.
+ dnl Some packages like Emacs use --avoid=threadlib.
+ dnl Write the symbol in such a way that it does not cause 'aclocal' to pick
+ dnl the threadlib.m4 file that is installed in $PREFIX/share/aclocal/.
+ m4_ifdef([gl_][THREADLIB], [AC_REQUIRE([gl_][THREADLIB])])
LIB_TIMER_TIME=
AC_SUBST([LIB_TIMER_TIME])
AC_SEARCH_LIBS([timer_settime], [rt posix4],
[test "$ac_cv_search_timer_settime" = "none required" ||
LIB_TIMER_TIME=$ac_cv_search_timer_settime])
- dnl GLIBC uses threads to emulate posix timers when kernel support
- dnl is not available (like Linux < 2.6 or when used with kFreeBSD)
- dnl Now the pthread lib is linked automatically in the normal case,
- dnl but when linking statically, it needs to be explicitly specified.
- AC_EGREP_CPP([Thread],
- [
-#include <features.h>
-#ifdef __GNU_LIBRARY__
- #if ((__GLIBC__ == 2 && __GLIBC_MINOR__ >= 2) || (__GLIBC__ > 2)) \
- && !defined __UCLIBC__
- Thread emulation available
- #endif
-#endif
- ],
- [LIB_TIMER_TIME="$LIB_TIMER_TIME $LIBMULTITHREAD"])
+ m4_ifdef([gl_][THREADLIB],
+ [dnl GLIBC uses threads to emulate posix timers when kernel support
+ dnl is not available (like Linux < 2.6 or when used with kFreeBSD)
+ dnl Now the pthread lib is linked automatically in the normal case,
+ dnl but when linking statically, it needs to be explicitly specified.
+ AC_EGREP_CPP([Thread],
+ [#include <features.h>
+ #ifdef __GNU_LIBRARY__
+ #if ((__GLIBC__ == 2 && __GLIBC_MINOR__ >= 2) || (__GLIBC__ > 2)) \
+ && !(__UCLIBC__ && __HAS_NO_THREADS__)
+ Thread emulation available
+ #endif
+ #endif
+ ],
+ [LIB_TIMER_TIME="$LIB_TIMER_TIME $LIBMULTITHREAD"])])
AC_CHECK_FUNCS([timer_settime])
LIBS=$gl_saved_libs
])