path: root/infra/libkookie/nixpkgs/pkgs/tools/misc/coreutils/coreutils-8.31-musl-cross.patch

From 453ff940449bbbde9ec00f0bbf82a359c5598fc7 Mon Sep 17 00:00:00 2001
From: Bruno Haible <bruno@clisp.org>
Date: Sat, 23 Mar 2019 23:00:52 +0100
Subject: [PATCH 1/1] Support cross-compilation to musl libc.

Reported by Necktwi Ozfguah <necktwi@ferryfair.com>.

* m4/calloc.m4 (_AC_FUNC_CALLOC_IF): Add cross-compilation guesses for
musl libc.
* m4/canonicalize.m4 (gl_FUNC_REALPATH_WORKS): Likewise.
* m4/chown.m4 (gl_FUNC_CHOWN): Likewise.
* m4/d-ino.m4 (gl_CHECK_TYPE_STRUCT_DIRENT_D_INO): Likewise.
* m4/fdopendir.m4 (gl_FUNC_FDOPENDIR): Likewise.
* m4/fnmatch.m4 (gl_FUNC_FNMATCH_POSIX): Likewise.
* m4/fpurge.m4 (gl_FUNC_FPURGE): Likewise.
* m4/getcwd.m4 (gl_FUNC_GETCWD_NULL): Likewise.
* m4/getcwd-abort-bug.m4 (gl_FUNC_GETCWD_ABORT_BUG): Likewise.
* m4/getdelim.m4 (gl_FUNC_GETDELIM): Likewise.
* m4/getgroups.m4 (AC_FUNC_GETGROUPS, gl_FUNC_GETGROUPS): Likewise.
* m4/getline.m4 (gl_FUNC_GETLINE): Likewise.
* m4/gettimeofday.m4 (gl_FUNC_GETTIMEOFDAY_CLOBBER): Likewise.
* m4/hypot.m4 (gl_FUNC_HYPOT): Likewise.  // removed
* m4/hypotf.m4 (gl_FUNC_HYPOTF): Likewise.  // removed
* m4/hypotl.m4 (gl_FUNC_HYPOTL): Likewise.  // removed
* m4/iconv_open-utf.m4 (gl_FUNC_ICONV_OPEN_UTF_SUPPORT): Likewise.  // removed
* m4/link-follow.m4 (gl_FUNC_LINK_FOLLOWS_SYMLINK): Likewise.
* m4/log.m4 (gl_FUNC_LOG): Likewise.  // removed
* m4/logf.m4 (gl_FUNC_LOGF): Likewise.  // removed
* m4/logl.m4 (gl_FUNC_LOGL_WORKS): Likewise.  // removed
* m4/log10.m4 (gl_FUNC_LOG10): Likewise.  // removed
* m4/log10f.m4 (gl_FUNC_LOG10F): Likewise.  // removed
* m4/log10l.m4 (gl_FUNC_LOG10L): Likewise.  // removed
* m4/log1p.m4 (gl_FUNC_LOG1P): Likewise.  // removed
* m4/log1pf.m4 (gl_FUNC_LOG1PF): Likewise.  // removed
* m4/log1pl.m4 (gl_FUNC_LOG1PL): Likewise.  // removed
* m4/log2.m4 (gl_FUNC_LOG2): Likewise.  // removed
* m4/log2f.m4 (gl_FUNC_LOG2F): Likewise.  // removed
* m4/malloc.m4 (_AC_FUNC_MALLOC_IF): Likewise.
* m4/mkdir.m4 (gl_FUNC_MKDIR): Likewise.
* m4/mkstemp.m4 (gl_FUNC_MKSTEMP): Likewise.
* m4/modf.m4 (gl_FUNC_MODF): Likewise.  // removed
* m4/modff.m4 (gl_FUNC_MODFF): Likewise.  // removed
* m4/modfl.m4 (gl_FUNC_MODFL): Likewise.  // removed
* m4/perror.m4 (gl_FUNC_PERROR): Likewise.
* m4/printf.m4 (gl_PRINTF_SIZES_C99, gl_PRINTF_INFINITE,
gl_PRINTF_INFINITE_LONG_DOUBLE, gl_PRINTF_DIRECTIVE_A,
gl_PRINTF_DIRECTIVE_F, gl_PRINTF_FLAG_ZERO, gl_SNPRINTF_TRUNCATION_C99,
gl_SNPRINTF_RETVAL_C99, gl_SNPRINTF_DIRECTIVE_N,
gl_VSNPRINTF_ZEROSIZE_C99): Likewise.
* m4/ptsname.m4 (gl_FUNC_PTSNAME): Likewise.  // removed
* m4/putenv.m4 (gl_FUNC_PUTENV): Likewise.
* m4/realloc.m4 (_AC_FUNC_REALLOC_IF): Likewise.
* m4/remainder.m4 (gl_FUNC_REMAINDER): Likewise.  // removed
* m4/remainderf.m4 (gl_FUNC_REMAINDERF): Likewise.  // removed
* m4/remainderl.m4 (gl_FUNC_REMAINDERL): Likewise.  // removed
* m4/rintl.m4 (gl_FUNC_RINTL): Likewise.  // removed
* m4/round.m4 (gl_FUNC_ROUND): Likewise.  // removed
* m4/roundf.m4 (gl_FUNC_ROUNDF): Likewise.  // removed
* m4/roundl.m4 (gl_FUNC_ROUNDL): Likewise.  // removed
* m4/setenv.m4 (gl_FUNC_SETENV): Likewise.
* m4/signbit.m4 (gl_SIGNBIT): Likewise.
* m4/sleep.m4 (gl_FUNC_SLEEP): Likewise.
* m4/stpncpy.m4 (gl_FUNC_STPNCPY): Likewise.
* m4/strerror.m4 (gl_FUNC_STRERROR, gl_FUNC_STRERROR_0): Likewise.
* m4/strtod.m4 (gl_FUNC_STRTOD): Likewise.
* m4/strtold.m4 (gl_FUNC_STRTOLD): Likewise.
* m4/trunc.m4 (gl_FUNC_TRUNC): Likewise.    // removed
* m4/truncf.m4 (gl_FUNC_TRUNCF): Likewise.  // removed
* m4/truncl.m4 (gl_FUNC_TRUNCL): Likewise.  // removed
* m4/tzset.m4 (gl_FUNC_TZSET_CLOBBER): Likewise.
* m4/ungetc.m4 (gl_FUNC_UNGETC_WORKS): Likewise.
* m4/usleep.m4 (gl_FUNC_USLEEP): Likewise.
* m4/utimes.m4 (gl_FUNC_UTIMES): Likewise.
* m4/wcwidth.m4 (gl_FUNC_WCWIDTH): Likewise.
---
 m4/calloc.m4           |  4 ++-
 m4/canonicalize.m4     |  4 ++-
 m4/chown.m4            | 22 +++++++------
 m4/d-ino.m4            | 16 +++++-----
 m4/fdopendir.m4        | 12 ++++---
 m4/fnmatch.m4          | 18 ++++++++---
 m4/fpurge.m4           | 24 +++++++++-----
 m4/getcwd-abort-bug.m4 | 11 +++++--
 m4/getcwd.m4           |  4 ++-
 m4/getdelim.m4         | 40 ++++++++++++++----------
 m4/getgroups.m4        |  6 +++-
 m4/getline.m4          | 38 +++++++++++++---------
 m4/gettimeofday.m4     |  4 ++-
 m4/link-follow.m4      |  4 ++-
 m4/malloc.m4           |  4 +--
 m4/mkdir.m4            |  4 ++-
 m4/mkstemp.m4          |  4 ++-
 m4/perror.m4           | 12 ++++---
 m4/printf.m4           | 22 ++++++++++++-
 m4/putenv.m4           |  4 ++-
 m4/realloc.m4          |  4 +--
 m4/setenv.m4           |  4 ++-
 m4/signbit.m4          |  6 +++-
 m4/sleep.m4            |  4 ++-
 m4/stpncpy.m4          | 14 +++++++--
 m4/strerror.m4         |  6 +++-
 m4/strtod.m4           | 10 +++---
 m4/strtold.m4          |  9 ++++--
 m4/tzset.m4            |  4 ++-
 m4/ungetc.m4           | 18 ++++++-----
 m4/usleep.m4           |  4 ++-
 m4/utimes.m4           | 10 +++---
 m4/wcwidth.m4          | 12 ++++---
 76 files changed, 461 insertions(+), 157 deletions(-)

diff --git a/m4/calloc.m4 b/m4/calloc.m4
index 012a5bf..d76535d 100644
--- a/m4/calloc.m4
+++ b/m4/calloc.m4
@@ -1,4 +1,4 @@
-# calloc.m4 serial 18
+# calloc.m4 serial 19

 # Copyright (C) 2004-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -40,6 +40,8 @@ AC_DEFUN([_AC_FUNC_CALLOC_IF],
        [case "$host_os" in
                          # Guess yes on glibc systems.
           *-gnu* | gnu*) ac_cv_func_calloc_0_nonnull="guessing yes" ;;
+                         # Guess yes on musl systems.
+          *-musl*)       ac_cv_func_calloc_0_nonnull="guessing yes" ;;
                          # Guess yes on native Windows.
           mingw*)        ac_cv_func_calloc_0_nonnull="guessing yes" ;;
                          # If we don't know, assume the worst.
diff --git a/m4/canonicalize.m4 b/m4/canonicalize.m4
index 5b6e25d..b61747b 100644
--- a/m4/canonicalize.m4
+++ b/m4/canonicalize.m4
@@ -1,4 +1,4 @@
-# canonicalize.m4 serial 29
+# canonicalize.m4 serial 30

 dnl Copyright (C) 2003-2007, 2009-2019 Free Software Foundation, Inc.

@@ -113,6 +113,8 @@ AC_DEFUN([gl_FUNC_REALPATH_WORKS],
      [case "$host_os" in
                        # Guess yes on glibc systems.
         *-gnu* | gnu*) gl_cv_func_realpath_works="guessing yes" ;;
+                       # Guess yes on musl systems.
+        *-musl*)       gl_cv_func_realpath_works="guessing yes" ;;
                        # Guess no on native Windows.
         mingw*)        gl_cv_func_realpath_works="guessing no" ;;
                        # If we don't know, assume the worst.
diff --git a/m4/chown.m4 b/m4/chown.m4
index ecfc0c0..b798325 100644
--- a/m4/chown.m4
+++ b/m4/chown.m4
@@ -1,4 +1,4 @@
-# serial 30
+# serial 32
 # Determine whether we need the chown wrapper.

 dnl Copyright (C) 1997-2001, 2003-2005, 2007, 2009-2019 Free Software
@@ -109,10 +109,12 @@ AC_DEFUN_ONCE([gl_FUNC_CHOWN],
         [gl_cv_func_chown_slash_works=yes],
         [gl_cv_func_chown_slash_works=no],
         [case "$host_os" in
-                   # Guess yes on glibc systems.
-           *-gnu*) gl_cv_func_chown_slash_works="guessing yes" ;;
-                   # If we don't know, assume the worst.
-           *)      gl_cv_func_chown_slash_works="guessing no" ;;
+                    # Guess yes on glibc systems.
+           *-gnu*)  gl_cv_func_chown_slash_works="guessing yes" ;;
+                    # Guess yes on musl systems.
+           *-musl*) gl_cv_func_chown_slash_works="guessing yes" ;;
+                    # If we don't know, assume the worst.
+           *)       gl_cv_func_chown_slash_works="guessing no" ;;
          esac
         ])
       rm -f conftest.link conftest.file])
@@ -145,10 +147,12 @@ AC_DEFUN_ONCE([gl_FUNC_CHOWN],
         [gl_cv_func_chown_ctime_works=yes],
         [gl_cv_func_chown_ctime_works=no],
         [case "$host_os" in
-                   # Guess yes on glibc systems.
-           *-gnu*) gl_cv_func_chown_ctime_works="guessing yes" ;;
-                   # If we don't know, assume the worst.
-           *)      gl_cv_func_chown_ctime_works="guessing no" ;;
+                    # Guess yes on glibc systems.
+           *-gnu*)  gl_cv_func_chown_ctime_works="guessing yes" ;;
+                    # Guess yes on musl systems.
+           *-musl*) gl_cv_func_chown_ctime_works="guessing yes" ;;
+                    # If we don't know, assume the worst.
+           *)       gl_cv_func_chown_ctime_works="guessing no" ;;
          esac
         ])
       rm -f conftest.file])
diff --git a/m4/d-ino.m4 b/m4/d-ino.m4
index f1420cc..87dcacc 100644
--- a/m4/d-ino.m4
+++ b/m4/d-ino.m4
@@ -1,4 +1,4 @@
-# serial 18
+# serial 19

 dnl From Jim Meyering.
 dnl
@@ -40,12 +40,14 @@ AC_DEFUN([gl_CHECK_TYPE_STRUCT_DIRENT_D_INO],
            [gl_cv_struct_dirent_d_ino=yes],
            [gl_cv_struct_dirent_d_ino=no],
            [case "$host_os" in
-                           # Guess yes on glibc systems with Linux kernel.
-              linux*-gnu*) gl_cv_struct_dirent_d_ino="guessing yes" ;;
-                           # Guess no on native Windows.
-              mingw*)      gl_cv_struct_dirent_d_ino="guessing no" ;;
-                           # If we don't know, assume the worst.
-              *)           gl_cv_struct_dirent_d_ino="guessing no" ;;
+                            # Guess yes on glibc systems with Linux kernel.
+              linux*-gnu*)  gl_cv_struct_dirent_d_ino="guessing yes" ;;
+                            # Guess yes on musl systems with Linux kernel.
+              linux*-musl*) gl_cv_struct_dirent_d_ino="guessing yes" ;;
+                            # Guess no on native Windows.
+              mingw*)       gl_cv_struct_dirent_d_ino="guessing no" ;;
+                            # If we don't know, assume the worst.
+              *)            gl_cv_struct_dirent_d_ino="guessing no" ;;
             esac
            ])])
    case "$gl_cv_struct_dirent_d_ino" in
diff --git a/m4/fdopendir.m4 b/m4/fdopendir.m4
index 0490551..b2b3b03 100644
--- a/m4/fdopendir.m4
+++ b/m4/fdopendir.m4
@@ -1,4 +1,4 @@
-# serial 10
+# serial 11
 # See if we need to provide fdopendir.

 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
@@ -45,10 +45,12 @@ DIR *fdopendir (int);
          [gl_cv_func_fdopendir_works=yes],
          [gl_cv_func_fdopendir_works=no],
          [case "$host_os" in
-                    # Guess yes on glibc systems.
-            *-gnu*) gl_cv_func_fdopendir_works="guessing yes" ;;
-                    # If we don't know, assume the worst.
-            *)      gl_cv_func_fdopendir_works="guessing no" ;;
+                     # Guess yes on glibc systems.
+            *-gnu*)  gl_cv_func_fdopendir_works="guessing yes" ;;
+                     # Guess yes on musl systems.
+            *-musl*) gl_cv_func_fdopendir_works="guessing yes" ;;
+                     # If we don't know, assume the worst.
+            *)       gl_cv_func_fdopendir_works="guessing no" ;;
           esac
          ])])
     case "$gl_cv_func_fdopendir_works" in
diff --git a/m4/fnmatch.m4 b/m4/fnmatch.m4
index c264ca7..75ba55b 100644
--- a/m4/fnmatch.m4
+++ b/m4/fnmatch.m4
@@ -1,4 +1,4 @@
-# Check for fnmatch - serial 13.  -*- coding: utf-8 -*-
+# Check for fnmatch - serial 14.  -*- coding: utf-8 -*-

 # Copyright (C) 2000-2007, 2009-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -14,6 +14,7 @@ AC_DEFUN([gl_FUNC_FNMATCH_POSIX],
   m4_divert_text([DEFAULTS], [gl_fnmatch_required=POSIX])

   AC_REQUIRE([gl_FNMATCH_H])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
   gl_fnmatch_required_lowercase=`
     echo $gl_fnmatch_required | LC_ALL=C tr '[[A-Z]]' '[[a-z]]'
   `
@@ -117,12 +118,19 @@ AC_DEFUN([gl_FUNC_FNMATCH_POSIX],
             ]])],
          [eval "$gl_fnmatch_cache_var=yes"],
          [eval "$gl_fnmatch_cache_var=no"],
-         [eval "$gl_fnmatch_cache_var=\"guessing no\""])
+         [case "$host_os" in
+                     # Guess yes on musl systems.
+            *-musl*) eval "$gl_fnmatch_cache_var=\"guessing yes\"" ;;
+                     # Guess no otherwise, even on glibc systems.
+            *)       eval "$gl_fnmatch_cache_var=\"guessing no\"" ;;
+          esac
+         ])
       ])
     eval "gl_fnmatch_result=\"\$$gl_fnmatch_cache_var\""
-    if test "$gl_fnmatch_result" != yes; then
-      REPLACE_FNMATCH=1
-    fi
+    case "$gl_fnmatch_result" in
+      *yes) ;;
+      *) REPLACE_FNMATCH=1 ;;
+    esac
   fi
   if test $HAVE_FNMATCH = 0 || test $REPLACE_FNMATCH = 1; then
     gl_REPLACE_FNMATCH_H
diff --git a/m4/fpurge.m4 b/m4/fpurge.m4
index cb21f56..6c5b3e9 100644
--- a/m4/fpurge.m4
+++ b/m4/fpurge.m4
@@ -1,4 +1,4 @@
-# fpurge.m4 serial 8
+# fpurge.m4 serial 9
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -7,12 +7,13 @@ dnl with or without modifications, as long as this notice is preserved.
 AC_DEFUN([gl_FUNC_FPURGE],
 [
   AC_REQUIRE([gl_STDIO_H_DEFAULTS])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
   AC_CHECK_FUNCS_ONCE([fpurge])
   AC_CHECK_FUNCS_ONCE([__fpurge])
   AC_CHECK_DECLS([fpurge], , , [[#include <stdio.h>]])
   if test "x$ac_cv_func_fpurge" = xyes; then
     HAVE_FPURGE=1
-    # Detect BSD bug.  Only cygwin 1.7 is known to be immune.
+    # Detect BSD bug.  Only cygwin 1.7 and musl are known to be immune.
     AC_CACHE_CHECK([whether fpurge works], [gl_cv_func_fpurge_works],
       [AC_RUN_IFELSE(
          [AC_LANG_PROGRAM(
@@ -48,11 +49,20 @@ AC_DEFUN([gl_FUNC_FPURGE],
                return 13;
              return 0;
             ])],
-      [gl_cv_func_fpurge_works=yes], [gl_cv_func_fpurge_works=no],
-      [gl_cv_func_fpurge_works='guessing no'])])
-    if test "x$gl_cv_func_fpurge_works" != xyes; then
-      REPLACE_FPURGE=1
-    fi
+         [gl_cv_func_fpurge_works=yes],
+         [gl_cv_func_fpurge_works=no],
+         [case "$host_os" in
+                     # Guess yes on musl systems.
+            *-musl*) gl_cv_func_fpurge_works="guessing yes" ;;
+                     # Guess no otherwise.
+            *)       gl_cv_func_fpurge_works="guessing no" ;;
+          esac
+         ])
+      ])
+    case "$gl_cv_func_fpurge_works" in
+      *yes) ;;
+      *) REPLACE_FPURGE=1 ;;
+    esac
   else
     HAVE_FPURGE=0
   fi
diff --git a/m4/getcwd-abort-bug.m4 b/m4/getcwd-abort-bug.m4
index f0f24a5..7227f08 100644
--- a/m4/getcwd-abort-bug.m4
+++ b/m4/getcwd-abort-bug.m4
@@ -1,4 +1,4 @@
-# serial 9
+# serial 11
 # Determine whether getcwd aborts when the length of the working directory
 # name is unusually large.  Any length between 4k and 16k trigger the bug
 # when using glibc-2.4.90-9 or older.
@@ -13,6 +13,7 @@
 # gl_FUNC_GETCWD_ABORT_BUG([ACTION-IF-FOUND[, ACTION-IF-NOT-FOUND]])
 AC_DEFUN([gl_FUNC_GETCWD_ABORT_BUG],
 [
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
   AC_CHECK_DECLS_ONCE([getcwd])
   AC_CHECK_HEADERS_ONCE([unistd.h])
   AC_REQUIRE([gl_PATHMAX_SNIPPET_PREREQ])
@@ -142,7 +143,13 @@ main ()
         else
           gl_cv_func_getcwd_abort_bug=no
         fi],
-       [gl_cv_func_getcwd_abort_bug=yes])
+       [case "$host_os" in
+                   # Guess no on musl systems.
+          *-musl*) gl_cv_func_getcwd_abort_bug="guessing no" ;;
+                   # Guess yes otherwise, even on glibc systems.
+          *)       gl_cv_func_getcwd_abort_bug="guessing yes"
+        esac
+       ])
     ])
   AS_IF([test $gl_cv_func_getcwd_abort_bug = yes], [$1], [$2])
 ])
diff --git a/m4/getcwd.m4 b/m4/getcwd.m4
index 4929b51..625171a 100644
--- a/m4/getcwd.m4
+++ b/m4/getcwd.m4
@@ -6,7 +6,7 @@
 # with or without modifications, as long as this notice is preserved.

 # Written by Paul Eggert.
-# serial 16
+# serial 17

 AC_DEFUN([gl_FUNC_GETCWD_NULL],
   [
@@ -50,6 +50,8 @@ AC_DEFUN([gl_FUNC_GETCWD_NULL],
         [[case "$host_os" in
                            # Guess yes on glibc systems.
             *-gnu* | gnu*) gl_cv_func_getcwd_null="guessing yes";;
+                           # Guess yes on musl systems.
+            *-musl*)       gl_cv_func_getcwd_null="guessing yes";;
                            # Guess yes on Cygwin.
             cygwin*)       gl_cv_func_getcwd_null="guessing yes";;
                            # If we don't know, assume the worst.
diff --git a/m4/getdelim.m4 b/m4/getdelim.m4
index bf17c57..e77c379 100644
--- a/m4/getdelim.m4
+++ b/m4/getdelim.m4
@@ -1,4 +1,4 @@
-# getdelim.m4 serial 12
+# getdelim.m4 serial 13

 dnl Copyright (C) 2005-2007, 2009-2019 Free Software Foundation, Inc.
 dnl
@@ -11,6 +11,7 @@ AC_PREREQ([2.59])
 AC_DEFUN([gl_FUNC_GETDELIM],
 [
   AC_REQUIRE([gl_STDIO_H_DEFAULTS])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles

   dnl Persuade glibc <stdio.h> to declare getdelim().
   AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
@@ -21,9 +22,10 @@ AC_DEFUN([gl_FUNC_GETDELIM],
   if test $ac_cv_func_getdelim = yes; then
     HAVE_GETDELIM=1
     dnl Found it in some library.  Verify that it works.
-    AC_CACHE_CHECK([for working getdelim function], [gl_cv_func_working_getdelim],
-    [echo fooNbarN | tr -d '\012' | tr N '\012' > conftest.data
-    AC_RUN_IFELSE([AC_LANG_SOURCE([[
+    AC_CACHE_CHECK([for working getdelim function],
+      [gl_cv_func_working_getdelim],
+      [echo fooNbarN | tr -d '\012' | tr N '\012' > conftest.data
+       AC_RUN_IFELSE([AC_LANG_SOURCE([[
 #    include <stdio.h>
 #    include <stdlib.h>
 #    include <string.h>
@@ -53,25 +55,31 @@ AC_DEFUN([gl_FUNC_GETDELIM],
       fclose (in);
       return 0;
     }
-    ]])], [gl_cv_func_working_getdelim=yes] dnl The library version works.
-    , [gl_cv_func_working_getdelim=no] dnl The library version does NOT work.
-    , dnl We're cross compiling. Assume it works on glibc2 systems.
-      [AC_EGREP_CPP([Lucky GNU user],
-         [
+    ]])],
+         [gl_cv_func_working_getdelim=yes],
+         [gl_cv_func_working_getdelim=no],
+         [dnl We're cross compiling.
+          dnl Guess it works on glibc2 systems and musl systems.
+          AC_EGREP_CPP([Lucky GNU user],
+            [
 #include <features.h>
 #ifdef __GNU_LIBRARY__
  #if (__GLIBC__ >= 2) && !defined __UCLIBC__
   Lucky GNU user
  #endif
 #endif
-         ],
-         [gl_cv_func_working_getdelim="guessing yes"],
-         [gl_cv_func_working_getdelim="guessing no"])]
-    )])
+            ],
+            [gl_cv_func_working_getdelim="guessing yes"],
+            [case "$host_os" in
+               *-musl*) gl_cv_func_working_getdelim="guessing yes" ;;
+               *)       gl_cv_func_working_getdelim="guessing no" ;;
+             esac
+            ])
+         ])
+      ])
     case "$gl_cv_func_working_getdelim" in
-      *no)
-        REPLACE_GETDELIM=1
-        ;;
+      *yes) ;;
+      *) REPLACE_GETDELIM=1 ;;
     esac
   else
     HAVE_GETDELIM=0
diff --git a/m4/getgroups.m4 b/m4/getgroups.m4
index 2ce986e..c93447b 100644
--- a/m4/getgroups.m4
+++ b/m4/getgroups.m4
@@ -1,4 +1,4 @@
-# serial 21
+# serial 22

 dnl From Jim Meyering.
 dnl A wrapper around AC_FUNC_GETGROUPS.
@@ -42,6 +42,8 @@ AC_DEFUN([AC_FUNC_GETGROUPS],
          [case "$host_os" in # ((
                            # Guess yes on glibc systems.
             *-gnu* | gnu*) ac_cv_func_getgroups_works="guessing yes" ;;
+                           # Guess yes on musl systems.
+            *-musl*)       ac_cv_func_getgroups_works="guessing yes" ;;
                            # If we don't know, assume the worst.
             *)             ac_cv_func_getgroups_works="guessing no" ;;
           esac
@@ -95,6 +97,8 @@ AC_DEFUN([gl_FUNC_GETGROUPS],
           [case "$host_os" in
                             # Guess yes on glibc systems.
              *-gnu* | gnu*) gl_cv_func_getgroups_works="guessing yes" ;;
+                            # Guess yes on musl systems.
+             *-musl*)       gl_cv_func_getgroups_works="guessing yes" ;;
                             # If we don't know, assume the worst.
              *)             gl_cv_func_getgroups_works="guessing no" ;;
            esac
diff --git a/m4/getline.m4 b/m4/getline.m4
index 5b2ead2..32f771c 100644
--- a/m4/getline.m4
+++ b/m4/getline.m4
@@ -1,4 +1,4 @@
-# getline.m4 serial 28
+# getline.m4 serial 29

 dnl Copyright (C) 1998-2003, 2005-2007, 2009-2019 Free Software Foundation,
 dnl Inc.
@@ -16,6 +16,7 @@ dnl to do with the function we need.
 AC_DEFUN([gl_FUNC_GETLINE],
 [
   AC_REQUIRE([gl_STDIO_H_DEFAULTS])
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles

   dnl Persuade glibc <stdio.h> to declare getline().
   AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
@@ -28,9 +29,10 @@ AC_DEFUN([gl_FUNC_GETLINE],
                  gl_getline_needs_run_time_check=yes],
                 [am_cv_func_working_getline=no])
   if test $gl_getline_needs_run_time_check = yes; then
-    AC_CACHE_CHECK([for working getline function], [am_cv_func_working_getline],
-    [echo fooNbarN | tr -d '\012' | tr N '\012' > conftest.data
-    AC_RUN_IFELSE([AC_LANG_SOURCE([[
+    AC_CACHE_CHECK([for working getline function],
+      [am_cv_func_working_getline],
+      [echo fooNbarN | tr -d '\012' | tr N '\012' > conftest.data
+       AC_RUN_IFELSE([AC_LANG_SOURCE([[
 #    include <stdio.h>
 #    include <stdlib.h>
 #    include <string.h>
@@ -61,21 +63,28 @@ AC_DEFUN([gl_FUNC_GETLINE],
       fclose (in);
       return 0;
     }
-    ]])], [am_cv_func_working_getline=yes] dnl The library version works.
-    , [am_cv_func_working_getline=no] dnl The library version does NOT work.
-    , dnl We're cross compiling. Assume it works on glibc2 systems.
-      [AC_EGREP_CPP([Lucky GNU user],
-         [
+    ]])],
+         [am_cv_func_working_getline=yes],
+         [am_cv_func_working_getline=no],
+         [dnl We're cross compiling.
+          dnl Guess it works on glibc2 systems and musl systems.
+          AC_EGREP_CPP([Lucky GNU user],
+            [
 #include <features.h>
 #ifdef __GNU_LIBRARY__
  #if (__GLIBC__ >= 2) && !defined __UCLIBC__
   Lucky GNU user
  #endif
 #endif
-         ],
-         [am_cv_func_working_getline="guessing yes"],
-         [am_cv_func_working_getline="guessing no"])]
-    )])
+            ],
+            [am_cv_func_working_getline="guessing yes"],
+            [case "$host_os" in
+               *-musl*) am_cv_func_working_getline="guessing yes" ;;
+               *)       am_cv_func_working_getline="guessing no" ;;
+             esac
+            ])
+         ])
+      ])
   fi

   if test $ac_cv_have_decl_getline = no; then
@@ -83,7 +92,8 @@ AC_DEFUN([gl_FUNC_GETLINE],
   fi

   case "$am_cv_func_working_getline" in
-    *no)
+    *yes) ;;
+    *)
       dnl Set REPLACE_GETLINE always: Even if we have not found the broken
       dnl getline function among $LIBS, it may exist in libinet and the
       dnl executable may be linked with -linet.
diff --git a/m4/gettimeofday.m4 b/m4/gettimeofday.m4
index d29b4bf..5e2ef6f 100644
--- a/m4/gettimeofday.m4
+++ b/m4/gettimeofday.m4
@@ -1,4 +1,4 @@
-# serial 25
+# serial 26

 # Copyright (C) 2001-2003, 2005, 2007, 2009-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -105,6 +105,8 @@ AC_DEFUN([gl_FUNC_GETTIMEOFDAY_CLOBBER],
       case "$host_os" in
                        # Guess all is fine on glibc systems.
         *-gnu* | gnu*) gl_cv_func_gettimeofday_clobber="guessing no" ;;
+                       # Guess all is fine on musl systems.
+        *-musl*)       gl_cv_func_gettimeofday_clobber="guessing no" ;;
                        # Guess no on native Windows.
         mingw*)        gl_cv_func_gettimeofday_clobber="guessing no" ;;
                        # If we don't know, assume the worst.
diff --git a/m4/link-follow.m4 b/m4/link-follow.m4
index cbd2dca..8ac7301 100644
--- a/m4/link-follow.m4
+++ b/m4/link-follow.m4
@@ -1,4 +1,4 @@
-# serial 20
+# serial 21
 dnl Run a program to determine whether link(2) follows symlinks.
 dnl Set LINK_FOLLOWS_SYMLINKS accordingly.

@@ -88,6 +88,8 @@ AC_DEFUN([gl_FUNC_LINK_FOLLOWS_SYMLINK],
             case "$host_os" in
                                   # On glibc/Linux we know the result.
               linux*-gnu* | gnu*) gl_cv_func_link_follows_symlink="guessing no" ;;
+                                  # On musl/Linux we know the result.
+              linux*-musl*)       gl_cv_func_link_follows_symlink="guessing no" ;;
                                   # Otherwise, we don't know.
               *)                  gl_cv_func_link_follows_symlink=unknown ;;
             esac
diff --git a/m4/malloc.m4 b/m4/malloc.m4
index b9b8d4b..c469c45 100644
--- a/m4/malloc.m4
+++ b/m4/malloc.m4
@@ -1,4 +1,4 @@
-# malloc.m4 serial 17
+# malloc.m4 serial 19
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -32,7 +32,7 @@ AC_DEFUN([_AC_FUNC_MALLOC_IF],
        [ac_cv_func_malloc_0_nonnull=no],
        [case "$host_os" in
           # Guess yes on platforms where we know the result.
-          *-gnu* | gnu* | freebsd* | netbsd* | openbsd* \
+          *-gnu* | gnu* | *-musl* | freebsd* | netbsd* | openbsd* \
           | hpux* | solaris* | cygwin* | mingw*)
             ac_cv_func_malloc_0_nonnull="guessing yes" ;;
           # If we don't know, assume the worst.
diff --git a/m4/mkdir.m4 b/m4/mkdir.m4
index 4cd9590..366a3cd 100644
--- a/m4/mkdir.m4
+++ b/m4/mkdir.m4
@@ -1,4 +1,4 @@
-# serial 14
+# serial 15

 # Copyright (C) 2001, 2003-2004, 2006, 2008-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -62,6 +62,8 @@ AC_DEFUN([gl_FUNC_MKDIR],
       [case "$host_os" in
                         # Guess yes on glibc systems.
          *-gnu* | gnu*) gl_cv_func_mkdir_trailing_dot_works="guessing yes" ;;
+                        # Guess yes on musl systems.
+         *-musl*)       gl_cv_func_mkdir_trailing_dot_works="guessing yes" ;;
                         # Guess no on native Windows.
          mingw*)        gl_cv_func_mkdir_trailing_dot_works="guessing no" ;;
                         # If we don't know, assume the worst.
diff --git a/m4/mkstemp.m4 b/m4/mkstemp.m4
index ae24c3b..1b15c2e 100644
--- a/m4/mkstemp.m4
+++ b/m4/mkstemp.m4
@@ -1,4 +1,4 @@
-#serial 25
+#serial 26

 # Copyright (C) 2001, 2003-2007, 2009-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -59,6 +59,8 @@ AC_DEFUN([gl_FUNC_MKSTEMP],
           [case "$host_os" in
                             # Guess yes on glibc systems.
              *-gnu* | gnu*) gl_cv_func_working_mkstemp="guessing yes" ;;
+                            # Guess yes on musl systems.
+             *-musl*)       gl_cv_func_working_mkstemp="guessing yes" ;;
                             # Guess no on native Windows.
              mingw*)        gl_cv_func_working_mkstemp="guessing no" ;;
                             # If we don't know, assume the worst.
diff --git a/m4/perror.m4 b/m4/perror.m4
index 335be72..08e2db1 100644
--- a/m4/perror.m4
+++ b/m4/perror.m4
@@ -1,4 +1,4 @@
-# perror.m4 serial 7
+# perror.m4 serial 8
 dnl Copyright (C) 2008-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -48,10 +48,12 @@ AC_DEFUN([gl_FUNC_PERROR],
             rm -rf conftest.txt1 conftest.txt2],
            [gl_cv_func_perror_works=no],
            [case "$host_os" in
-                      # Guess yes on native Windows.
-              mingw*) gl_cv_func_perror_works="guessing yes" ;;
-                      # Otherwise guess no.
-              *)      gl_cv_func_perror_works="guessing no" ;;
+                       # Guess yes on musl systems.
+              *-musl*) gl_cv_func_perror_works="guessing yes" ;;
+                       # Guess yes on native Windows.
+              mingw*)  gl_cv_func_perror_works="guessing yes" ;;
+                       # Otherwise guess no.
+              *)       gl_cv_func_perror_works="guessing no" ;;
             esac
            ])
         ])
diff --git a/m4/printf.m4 b/m4/printf.m4
index cbf6ae4..6d2280e 100644
--- a/m4/printf.m4
+++ b/m4/printf.m4
@@ -1,4 +1,4 @@
-# printf.m4 serial 60
+# printf.m4 serial 61
 dnl Copyright (C) 2003, 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,
@@ -62,6 +62,8 @@ int main ()
 changequote(,)dnl
                                  # Guess yes on glibc systems.
            *-gnu* | gnu*)        gl_cv_func_printf_sizes_c99="guessing yes";;
+                                 # Guess yes on musl systems.
+           *-musl*)              gl_cv_func_printf_sizes_c99="guessing yes";;
                                  # Guess yes on FreeBSD >= 5.
            freebsd[1-4].*)       gl_cv_func_printf_sizes_c99="guessing no";;
            freebsd* | kfreebsd*) gl_cv_func_printf_sizes_c99="guessing yes";;
@@ -240,6 +242,8 @@ int main ()
 changequote(,)dnl
                                  # Guess yes on glibc systems.
            *-gnu* | gnu*)        gl_cv_func_printf_infinite="guessing yes";;
+                                 # Guess yes on musl systems.
+           *-musl*)              gl_cv_func_printf_infinite="guessing yes";;
                                  # Guess yes on FreeBSD >= 6.
            freebsd[1-5].*)       gl_cv_func_printf_infinite="guessing no";;
            freebsd* | kfreebsd*) gl_cv_func_printf_infinite="guessing yes";;
@@ -457,6 +461,8 @@ int main ()
 changequote(,)dnl
                                          # Guess yes on glibc systems.
                    *-gnu* | gnu*)        gl_cv_func_printf_infinite_long_double="guessing yes";;
+                                         # Guess yes on musl systems.
+                   *-musl*)              gl_cv_func_printf_infinite_long_double="guessing yes";;
                                          # Guess yes on FreeBSD >= 6.
                    freebsd[1-5].*)       gl_cv_func_printf_infinite_long_double="guessing no";;
                    freebsd* | kfreebsd*) gl_cv_func_printf_infinite_long_double="guessing yes";;
@@ -575,6 +581,8 @@ int main ()
                [gl_cv_func_printf_directive_a="guessing yes"],
                [gl_cv_func_printf_directive_a="guessing no"])
              ;;
+                                 # Guess yes on musl systems.
+           *-musl*)              gl_cv_func_printf_directive_a="guessing yes";;
                                  # Guess no on Android.
            linux*-android*)      gl_cv_func_printf_directive_a="guessing no";;
                                  # Guess no on native Windows.
@@ -625,6 +633,8 @@ int main ()
 changequote(,)dnl
                                  # Guess yes on glibc systems.
            *-gnu* | gnu*)        gl_cv_func_printf_directive_f="guessing yes";;
+                                 # Guess yes on musl systems.
+           *-musl*)              gl_cv_func_printf_directive_f="guessing yes";;
                                  # Guess yes on FreeBSD >= 6.
            freebsd[1-5].*)       gl_cv_func_printf_directive_f="guessing no";;
            freebsd* | kfreebsd*) gl_cv_func_printf_directive_f="guessing yes";;
@@ -960,6 +970,8 @@ changequote(,)dnl
          case "$host_os" in
                             # Guess yes on glibc systems.
            *-gnu* | gnu*)   gl_cv_func_printf_flag_zero="guessing yes";;
+                            # Guess yes on musl systems.
+           *-musl*)         gl_cv_func_printf_flag_zero="guessing yes";;
                             # Guess yes on BeOS.
            beos*)           gl_cv_func_printf_flag_zero="guessing yes";;
                             # Guess no on Android.
@@ -1206,6 +1218,8 @@ changequote(,)dnl
          case "$host_os" in
                                  # Guess yes on glibc systems.
            *-gnu* | gnu*)        gl_cv_func_snprintf_truncation_c99="guessing yes";;
+                                 # Guess yes on musl systems.
+           *-musl*)              gl_cv_func_snprintf_truncation_c99="guessing yes";;
                                  # Guess yes on FreeBSD >= 5.
            freebsd[1-4].*)       gl_cv_func_snprintf_truncation_c99="guessing no";;
            freebsd* | kfreebsd*) gl_cv_func_snprintf_truncation_c99="guessing yes";;
@@ -1308,6 +1322,8 @@ int main ()
 changequote(,)dnl
                                  # Guess yes on glibc systems.
            *-gnu* | gnu*)        gl_cv_func_snprintf_retval_c99="guessing yes";;
+                                 # Guess yes on musl systems.
+           *-musl*)              gl_cv_func_snprintf_retval_c99="guessing yes";;
                                  # Guess yes on FreeBSD >= 5.
            freebsd[1-4].*)       gl_cv_func_snprintf_retval_c99="guessing no";;
            freebsd* | kfreebsd*) gl_cv_func_snprintf_retval_c99="guessing yes";;
@@ -1400,6 +1416,8 @@ changequote(,)dnl
          case "$host_os" in
                                  # Guess yes on glibc systems.
            *-gnu* | gnu*)        gl_cv_func_snprintf_directive_n="guessing yes";;
+                                 # Guess yes on musl systems.
+           *-musl*)              gl_cv_func_snprintf_directive_n="guessing yes";;
                                  # Guess yes on FreeBSD >= 5.
            freebsd[1-4].*)       gl_cv_func_snprintf_directive_n="guessing no";;
            freebsd* | kfreebsd*) gl_cv_func_snprintf_directive_n="guessing yes";;
@@ -1554,6 +1572,8 @@ changequote(,)dnl
          case "$host_os" in
                                  # Guess yes on glibc systems.
            *-gnu* | gnu*)        gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
+                                 # Guess yes on musl systems.
+           *-musl*)              gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
                                  # Guess yes on FreeBSD >= 5.
            freebsd[1-4].*)       gl_cv_func_vsnprintf_zerosize_c99="guessing no";;
            freebsd* | kfreebsd*) gl_cv_func_vsnprintf_zerosize_c99="guessing yes";;
diff --git a/m4/putenv.m4 b/m4/putenv.m4
index f8960f6..342ba26 100644
--- a/m4/putenv.m4
+++ b/m4/putenv.m4
@@ -1,4 +1,4 @@
-# putenv.m4 serial 22
+# putenv.m4 serial 23
 dnl Copyright (C) 2002-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -36,6 +36,8 @@ AC_DEFUN([gl_FUNC_PUTENV],
              [case "$host_os" in
                                # Guess yes on glibc systems.
                 *-gnu* | gnu*) gl_cv_func_svid_putenv="guessing yes" ;;
+                               # Guess yes on musl systems.
+                *-musl*)       gl_cv_func_svid_putenv="guessing yes" ;;
                                # Guess no on native Windows.
                 mingw*)        gl_cv_func_svid_putenv="guessing no" ;;
                                # If we don't know, assume the worst.
diff --git a/m4/realloc.m4 b/m4/realloc.m4
index f9f15ad..93066e8 100644
--- a/m4/realloc.m4
+++ b/m4/realloc.m4
@@ -1,4 +1,4 @@
-# realloc.m4 serial 15
+# realloc.m4 serial 17
 dnl Copyright (C) 2007, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -32,7 +32,7 @@ AC_DEFUN([_AC_FUNC_REALLOC_IF],
        [ac_cv_func_realloc_0_nonnull=no],
        [case "$host_os" in
           # Guess yes on platforms where we know the result.
-          *-gnu* | gnu* | freebsd* | netbsd* | openbsd* \
+          *-gnu* | gnu* | *-musl* | freebsd* | netbsd* | openbsd* \
           | hpux* | solaris* | cygwin* | mingw*)
             ac_cv_func_realloc_0_nonnull="guessing yes" ;;
           # If we don't know, assume the worst.
diff --git a/m4/setenv.m4 b/m4/setenv.m4
index 6101274..a8f83d6 100644
--- a/m4/setenv.m4
+++ b/m4/setenv.m4
@@ -1,4 +1,4 @@
-# setenv.m4 serial 27
+# setenv.m4 serial 28
 dnl Copyright (C) 2001-2004, 2006-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -37,6 +37,8 @@ AC_DEFUN([gl_FUNC_SETENV],
       [case "$host_os" in
                         # Guess yes on glibc systems.
          *-gnu* | gnu*) gl_cv_func_setenv_works="guessing yes" ;;
+                        # Guess yes on musl systems.
+         *-musl*)       gl_cv_func_setenv_works="guessing yes" ;;
                         # If we don't know, assume the worst.
          *)             gl_cv_func_setenv_works="guessing no" ;;
        esac
diff --git a/m4/signbit.m4 b/m4/signbit.m4
index bf5bce5..f7f2f3d 100644
--- a/m4/signbit.m4
+++ b/m4/signbit.m4
@@ -1,4 +1,4 @@
-# signbit.m4 serial 16
+# signbit.m4 serial 17
 dnl Copyright (C) 2007-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -31,6 +31,8 @@ AC_DEFUN([gl_SIGNBIT],
         [case "$host_os" in
                           # Guess yes on glibc systems.
            *-gnu* | gnu*) gl_cv_func_signbit="guessing yes" ;;
+                          # Guess yes on musl systems.
+           *-musl*)       gl_cv_func_signbit="guessing yes" ;;
                           # Guess yes on native Windows.
            mingw*)        gl_cv_func_signbit="guessing yes" ;;
                           # If we don't know, assume the worst.
@@ -62,6 +64,8 @@ AC_DEFUN([gl_SIGNBIT],
         [case "$host_os" in
                           # Guess yes on glibc systems.
            *-gnu* | gnu*) gl_cv_func_signbit_gcc="guessing yes" ;;
+                          # Guess yes on musl systems.
+           *-musl*)       gl_cv_func_signbit_gcc="guessing yes" ;;
                           # Guess yes on mingw, no on MSVC.
            mingw*)        if test -n "$GCC"; then
                             gl_cv_func_signbit_gcc="guessing yes"
diff --git a/m4/sleep.m4 b/m4/sleep.m4
index 5f71cc7..7bab467 100644
--- a/m4/sleep.m4
+++ b/m4/sleep.m4
@@ -1,4 +1,4 @@
-# sleep.m4 serial 9
+# sleep.m4 serial 10
 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,
@@ -48,6 +48,8 @@ handle_alarm (int sig)
       [case "$host_os" in
                         # Guess yes on glibc systems.
          *-gnu* | gnu*) gl_cv_func_sleep_works="guessing yes" ;;
+                        # Guess yes on musl systems.
+         *-musl*)       gl_cv_func_sleep_works="guessing yes" ;;
                         # Guess no on native Windows.
          mingw*)        gl_cv_func_sleep_works="guessing no" ;;
                         # If we don't know, assume the worst.
diff --git a/m4/stpncpy.m4 b/m4/stpncpy.m4
index 83425dd..f8e1a7c 100644
--- a/m4/stpncpy.m4
+++ b/m4/stpncpy.m4
@@ -1,4 +1,4 @@
-# stpncpy.m4 serial 16
+# stpncpy.m4 serial 17
 dnl Copyright (C) 2002-2003, 2005-2007, 2009-2019 Free Software Foundation,
 dnl Inc.
 dnl This file is free software; the Free Software Foundation
@@ -7,6 +7,8 @@ dnl with or without modifications, as long as this notice is preserved.

 AC_DEFUN([gl_FUNC_STPNCPY],
 [
+  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
+
   dnl Persuade glibc <string.h> to declare stpncpy().
   AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])

@@ -69,12 +71,18 @@ int main ()
 ]])],
         [gl_cv_func_stpncpy=yes],
         [gl_cv_func_stpncpy=no],
-        [AC_EGREP_CPP([Thanks for using GNU], [
+        [dnl Guess yes on glibc systems and musl systems.
+         AC_EGREP_CPP([Thanks for using GNU], [
 #include <features.h>
 #ifdef __GNU_LIBRARY__
   Thanks for using GNU
 #endif
-], [gl_cv_func_stpncpy="guessing yes"], [gl_cv_func_stpncpy="guessing no"])
+],         [gl_cv_func_stpncpy="guessing yes"],
+           [case "$host_os" in
+              *-musl*) gl_cv_func_stpncpy="guessing yes" ;;
+              *)       gl_cv_func_stpncpy="guessing no" ;;
+            esac
+           ])
         ])
     ])
     case "$gl_cv_func_stpncpy" in
diff --git a/m4/strerror.m4 b/m4/strerror.m4
index b452f7f..2c90f31 100644
--- a/m4/strerror.m4
+++ b/m4/strerror.m4
@@ -1,4 +1,4 @@
-# strerror.m4 serial 19
+# strerror.m4 serial 20
 dnl Copyright (C) 2002, 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,
@@ -26,6 +26,8 @@ AC_DEFUN([gl_FUNC_STRERROR],
         [case "$host_os" in
                           # Guess yes on glibc systems.
            *-gnu* | gnu*) gl_cv_func_working_strerror="guessing yes" ;;
+                          # Guess yes on musl systems.
+           *-musl*)       gl_cv_func_working_strerror="guessing yes" ;;
                           # If we don't know, assume the worst.
            *)             gl_cv_func_working_strerror="guessing no" ;;
          esac
@@ -80,6 +82,8 @@ AC_DEFUN([gl_FUNC_STRERROR_0],
       [case "$host_os" in
                         # Guess yes on glibc systems.
          *-gnu* | gnu*) gl_cv_func_strerror_0_works="guessing yes" ;;
+                        # Guess yes on musl systems.
+         *-musl*)       gl_cv_func_strerror_0_works="guessing yes" ;;
                         # Guess yes on native Windows.
          mingw*)        gl_cv_func_strerror_0_works="guessing yes" ;;
                         # If we don't know, assume the worst.
diff --git a/m4/strtod.m4 b/m4/strtod.m4
index 9912217..d68ab75 100644
--- a/m4/strtod.m4
+++ b/m4/strtod.m4
@@ -1,4 +1,4 @@
-# strtod.m4 serial 24
+# strtod.m4 serial 25
 dnl Copyright (C) 2002-2003, 2006-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -115,9 +115,11 @@ numeric_equal (double x, double y)
            ],
            [gl_cv_func_strtod_works="guessing yes"],
            [case "$host_os" in
-                      # Guess yes on native Windows.
-              mingw*) gl_cv_func_strtod_works="guessing yes" ;;
-              *)      gl_cv_func_strtod_works="guessing no" ;;
+                       # Guess yes on musl systems.
+              *-musl*) gl_cv_func_strtod_works="guessing yes" ;;
+                       # Guess yes on native Windows.
+              mingw*)  gl_cv_func_strtod_works="guessing yes" ;;
+              *)       gl_cv_func_strtod_works="guessing no" ;;
             esac
            ])
         ])
diff --git a/m4/strtold.m4 b/m4/strtold.m4
index 16b4eda..17125fe 100644
--- a/m4/strtold.m4
+++ b/m4/strtold.m4
@@ -1,4 +1,4 @@
-# strtold.m4 serial 2
+# strtold.m4 serial 4
 dnl Copyright (C) 2002-2003, 2006-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -98,7 +98,12 @@ numeric_equal (long double x, long double y)
 #endif
            ],
            [gl_cv_func_strtold_works="guessing yes"],
-           [gl_cv_func_strtod_works="guessing no"])
+           [case "$host_os" in
+                       # Guess yes on musl systems.
+              *-musl*) gl_cv_func_strtold_works="guessing yes" ;;
+              *)       gl_cv_func_strtold_works="guessing no" ;;
+            esac
+           ])
         ])
       ])
     case "$gl_cv_func_strtold_works" in
diff --git a/m4/tzset.m4 b/m4/tzset.m4
index 1278801..afdfa8e 100644
--- a/m4/tzset.m4
+++ b/m4/tzset.m4
@@ -1,4 +1,4 @@
-# serial 11
+# serial 12

 # Copyright (C) 2003, 2007, 2009-2019 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -70,6 +70,8 @@ main ()
        [case "$host_os" in
                          # Guess all is fine on glibc systems.
           *-gnu* | gnu*) gl_cv_func_tzset_clobber="guessing no" ;;
+                         # Guess all is fine on musl systems.
+          *-musl*)       gl_cv_func_tzset_clobber="guessing no" ;;
                          # Guess no on native Windows.
           mingw*)        gl_cv_func_tzset_clobber="guessing no" ;;
                          # If we don't know, assume the worst.
diff --git a/m4/ungetc.m4 b/m4/ungetc.m4
index ab8757b..08baf33 100644
--- a/m4/ungetc.m4
+++ b/m4/ungetc.m4
@@ -1,4 +1,4 @@
-# ungetc.m4 serial 6
+# ungetc.m4 serial 7
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -41,12 +41,16 @@ AC_DEFUN_ONCE([gl_FUNC_UNGETC_WORKS],
            remove ("conftest.tmp");])],
         [gl_cv_func_ungetc_works=yes], [gl_cv_func_ungetc_works=no],
         [case "$host_os" in
-                                       # Guess yes on glibc and bionic systems.
-           *-gnu* | gnu* | *-android*) gl_cv_func_ungetc_works="guessing yes" ;;
-                                       # Guess yes on native Windows.
-           mingw*)                     gl_cv_func_ungetc_works="guessing yes" ;;
-                                       # If we don't know, assume the worst.
-           *)                          gl_cv_func_ungetc_works="guessing no" ;;
+                          # Guess yes on glibc systems.
+           *-gnu* | gnu*) gl_cv_func_ungetc_works="guessing yes" ;;
+                          # Guess yes on musl systems.
+           *-musl*)       gl_cv_func_ungetc_works="guessing yes" ;;
+                          # Guess yes on bionic systems.
+           *-android*)    gl_cv_func_ungetc_works="guessing yes" ;;
+                          # Guess yes on native Windows.
+           mingw*)        gl_cv_func_ungetc_works="guessing yes" ;;
+                          # If we don't know, assume the worst.
+           *)             gl_cv_func_ungetc_works="guessing no" ;;
          esac
         ])
     ])
diff --git a/m4/usleep.m4 b/m4/usleep.m4
index 59605a8..4a6bff0 100644
--- a/m4/usleep.m4
+++ b/m4/usleep.m4
@@ -1,4 +1,4 @@
-# usleep.m4 serial 5
+# usleep.m4 serial 6
 dnl Copyright (C) 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -31,6 +31,8 @@ AC_DEFUN([gl_FUNC_USLEEP],
         [case "$host_os" in
                           # Guess yes on glibc systems.
            *-gnu* | gnu*) gl_cv_func_usleep_works="guessing yes" ;;
+                          # Guess yes on musl systems.
+           *-musl*)       gl_cv_func_usleep_works="guessing yes" ;;
                           # Guess no on native Windows.
            mingw*)        gl_cv_func_usleep_works="guessing no" ;;
                           # If we don't know, assume the worst.
diff --git a/m4/utimes.m4 b/m4/utimes.m4
index 7209b6d..5806d8f 100644
--- a/m4/utimes.m4
+++ b/m4/utimes.m4
@@ -1,5 +1,5 @@
 # Detect some bugs in glibc's implementation of utimes.
-# serial 5
+# serial 6

 dnl Copyright (C) 2003-2005, 2009-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
@@ -143,9 +143,11 @@ main ()
        [gl_cv_func_working_utimes=yes],
        [gl_cv_func_working_utimes=no],
        [case "$host_os" in
-                  # Guess no on native Windows.
-          mingw*) gl_cv_func_working_utimes="guessing no" ;;
-          *)      gl_cv_func_working_utimes="guessing no" ;;
+                   # Guess yes on musl systems.
+          *-musl*) gl_cv_func_working_utimes="guessing yes" ;;
+                   # Guess no on native Windows.
+          mingw*)  gl_cv_func_working_utimes="guessing no" ;;
+          *)       gl_cv_func_working_utimes="guessing no" ;;
         esac
        ])
     ])
diff --git a/m4/wcwidth.m4 b/m4/wcwidth.m4
index baa2002..3952fd2 100644
--- a/m4/wcwidth.m4
+++ b/m4/wcwidth.m4
@@ -1,4 +1,4 @@
-# wcwidth.m4 serial 27
+# wcwidth.m4 serial 28
 dnl Copyright (C) 2006-2019 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -98,9 +98,13 @@ int main ()
           [
 changequote(,)dnl
            case "$host_os" in
-                                        # Guess yes on glibc and AIX 7 systems.
-             *-gnu* | gnu* | aix[7-9]*) gl_cv_func_wcwidth_works="guessing yes";;
-             *)                         gl_cv_func_wcwidth_works="guessing no";;
+                            # Guess yes on glibc systems.
+             *-gnu* | gnu*) gl_cv_func_wcwidth_works="guessing yes";;
+                            # Guess yes on musl systems.
+             *-musl*)       gl_cv_func_wcwidth_works="guessing yes";;
+                            # Guess yes on AIX 7 systems.
+             aix[7-9]*)     gl_cv_func_wcwidth_works="guessing yes";;
+             *)             gl_cv_func_wcwidth_works="guessing no";;
            esac
 changequote([,])dnl
           ])
--
1.9.1