1 files changed, 32 insertions, 5 deletions

diff --git a/gl/m4/nl_langinfo.m4 b/gl/m4/nl_langinfo.m4
index 25e2101..6ad32c8 100644
--- a/gl/m4/nl_langinfo.m4
+++ b/gl/m4/nl_langinfo.m4
@@ -1,5 +1,5 @@
-# nl_langinfo.m4 serial 5
-dnl Copyright (C) 2009-2013 Free Software Foundation, Inc.
+# nl_langinfo.m4 serial 8
+dnl Copyright (C) 2009-2021 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.
@@ -9,7 +9,10 @@ AC_DEFUN([gl_FUNC_NL_LANGINFO],
   AC_REQUIRE([gl_LANGINFO_H_DEFAULTS])
   AC_REQUIRE([gl_LANGINFO_H])
   AC_CHECK_FUNCS_ONCE([nl_langinfo])
-  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+  AC_REQUIRE([AC_CANONICAL_HOST])
+  AC_REQUIRE([gl_FUNC_SETLOCALE_NULL])
+  AC_REQUIRE([gl_PTHREADLIB])
+  AC_CHECK_HEADERS_ONCE([threads.h])
   if test $ac_cv_func_nl_langinfo = yes; then
     # On Irix 6.5, YESEXPR is defined, but nl_langinfo(YESEXPR) is broken.
     AC_CACHE_CHECK([whether YESEXPR works],
@@ -36,8 +39,19 @@ AC_DEFUN([gl_FUNC_NL_LANGINFO],
     AC_DEFINE_UNQUOTED([FUNC_NL_LANGINFO_YESEXPR_WORKS],
       [$FUNC_NL_LANGINFO_YESEXPR_WORKS],
       [Define to 1 if nl_langinfo (YESEXPR) returns a non-empty string.])
-    if test $HAVE_LANGINFO_CODESET = 1 && test $HAVE_LANGINFO_ERA = 1 \
-        && test $FUNC_NL_LANGINFO_YESEXPR_WORKS = 1; then
+    # On Solaris 10 and Solaris 11.3, nl_langinfo is not multithread-safe.
+    case "$host_os" in
+      solaris*) NL_LANGINFO_MTSAFE=0 ;;
+      *)        NL_LANGINFO_MTSAFE=1 ;;
+    esac
+    AC_DEFINE_UNQUOTED([NL_LANGINFO_MTSAFE], [$NL_LANGINFO_MTSAFE],
+      [Define to 1 if nl_langinfo is multithread-safe.])
+    if test $HAVE_LANGINFO_CODESET = 1 \
+       && test $HAVE_LANGINFO_T_FMT_AMPM = 1 \
+       && test $HAVE_LANGINFO_ALTMON = 1 \
+       && test $HAVE_LANGINFO_ERA = 1 \
+       && test $FUNC_NL_LANGINFO_YESEXPR_WORKS = 1 \
+       && test $NL_LANGINFO_MTSAFE = 1; then
       :
     else
       REPLACE_NL_LANGINFO=1
@@ -47,4 +61,17 @@ AC_DEFUN([gl_FUNC_NL_LANGINFO],
   else
     HAVE_NL_LANGINFO=0
   fi
+  if test $HAVE_NL_LANGINFO = 0 || test $HAVE_LANGINFO_CODESET = 0; then
+    LIB_NL_LANGINFO="$LIB_SETLOCALE_NULL"
+  else
+    LIB_NL_LANGINFO=
+  fi
+  dnl LIB_NL_LANGINFO is expected to be empty everywhere.
+  AC_SUBST([LIB_NL_LANGINFO])
+])
+
+# Prerequisites of lib/nl_langinfo-lock.c.
+AC_DEFUN([gl_PREREQ_NL_LANGINFO_LOCK],
+[
+  gl_VISIBILITY
 ])