Update from Gnulib

This incorporates:
2019-12-06 nstrftime: better width support for %N, %z
2019-12-03 Avoid hassles caused by [[noreturn]] in C++
2019-12-02 Fix mistakes in --enable-threads=isoc fixes from 2019-12-01
* admin/merge-gnulib (AVOIDED_MODULES): Avoid pthread-h.
* lib/_Noreturn.h, lib/nstrftime.c, m4/gnulib-common.m4:
* m4/timer_time.m4:
Copy from Gnulib.
* lib/gnulib.mk.in: Regenerate.

2 files changed, 13 insertions, 6 deletions

diff --git a/m4/gnulib-common.m4 b/m4/gnulib-common.m4
index 479c9de9eab..d8f0d3fb566 100644
--- a/m4/gnulib-common.m4
+++ b/m4/gnulib-common.m4
@@ -1,4 +1,4 @@
-# gnulib-common.m4 serial 45
+# gnulib-common.m4 serial 46
 dnl Copyright (C) 2007-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -19,7 +19,14 @@ AC_DEFUN([gl_COMMON_BODY], [
 #ifndef _Noreturn
 # if (defined __cplusplus \
       && ((201103 <= __cplusplus && !(__GNUC__ == 4 && __GNUC_MINOR__ == 7)) \
-          || (defined _MSC_VER && 1900 <= _MSC_VER)))
+          || (defined _MSC_VER && 1900 <= _MSC_VER)) \
+      && 0)
+    /* [[noreturn]] is not practically usable, because with it the syntax
+         extern _Noreturn void func (...);
+       would not be valid; such a declaration would only be valid with 'extern'
+       and '_Noreturn' swapped, or without the 'extern' keyword.  However, some
+       AIX system header files and several gnulib header files use precisely
+       this syntax with 'extern'.  */
 #  define _Noreturn [[noreturn]]
 # elif ((!defined __cplusplus || defined __clang__) \
         && (201112 <= (defined __STDC_VERSION__ ? __STDC_VERSION__ : 0)  \
diff --git a/m4/timer_time.m4 b/m4/timer_time.m4
index 2c9b93c63b8..347d04dbe45 100644
--- a/m4/timer_time.m4
+++ b/m4/timer_time.m4
@@ -1,4 +1,4 @@
-# timer_time.m4 serial 3
+# timer_time.m4 serial 4
 dnl Copyright (C) 2011-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -16,7 +16,7 @@ AC_DEFUN([gl_TIMER_TIME],
   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])])
+  m4_ifdef([gl_][PTHREADLIB], [AC_REQUIRE([gl_][PTHREADLIB])])
 
   LIB_TIMER_TIME=
   AC_SUBST([LIB_TIMER_TIME])
@@ -24,7 +24,7 @@ AC_DEFUN([gl_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])
-    m4_ifdef([gl_][THREADLIB],
+    m4_ifdef([gl_][PTHREADLIB],
       [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,
@@ -38,7 +38,7 @@ AC_DEFUN([gl_TIMER_TIME],
            #endif
           #endif
          ],
-         [LIB_TIMER_TIME="$LIB_TIMER_TIME $LIBMULTITHREAD"])])
+         [LIB_TIMER_TIME="$LIB_TIMER_TIME $LIBPMULTITHREAD"])])
     AC_CHECK_FUNCS([timer_settime])
   LIBS=$gl_saved_libs
 ])