Remove Gnulib putenv code

It’s not needed, since Emacs always uses the system putenv and all
platforms have putenv.  This improves on the fix for Bug#19874.
Suggested by Bruno Haible.
* admin/merge-gnulib (GNULIB_MODULES): Remove putenv.
* configure.ac: Remove workarounds for Gnulib putenv module.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.
* lib/putenv.c, m4/putenv.m4: Remove.

2 files changed, 0 insertions, 69 deletions

diff --git a/m4/gnulib-comp.m4 b/m4/gnulib-comp.m4
index cb3b89dd72f..48d8030f539 100644
--- a/m4/gnulib-comp.m4
+++ b/m4/gnulib-comp.m4
@@ -133,7 +133,6 @@ AC_DEFUN([gl_EARLY],
   # Code from module pipe2:
   # Code from module pselect:
   # Code from module pthread_sigmask:
-  # Code from module putenv:
   # Code from module qcopy-acl:
   # Code from module readlink:
   # Code from module readlinkat:
@@ -368,12 +367,6 @@ AC_DEFUN([gl_INIT],
     gl_PREREQ_PTHREAD_SIGMASK
   fi
   gl_SIGNAL_MODULE_INDICATOR([pthread_sigmask])
-  gl_FUNC_PUTENV
-  if test $REPLACE_PUTENV = 1; then
-    AC_LIBOBJ([putenv])
-    gl_PREREQ_PUTENV
-  fi
-  gl_STDLIB_MODULE_INDICATOR([putenv])
   gl_FUNC_READLINK
   if test $HAVE_READLINK = 0 || test $REPLACE_READLINK = 1; then
     AC_LIBOBJ([readlink])
@@ -973,7 +966,6 @@ AC_DEFUN([gl_FILE_LIST], [
   lib/pipe2.c
   lib/pselect.c
   lib/pthread_sigmask.c
-  lib/putenv.c
   lib/qcopy-acl.c
   lib/readlink.c
   lib/readlinkat.c
@@ -1112,7 +1104,6 @@ AC_DEFUN([gl_FILE_LIST], [
   m4/pipe2.m4
   m4/pselect.m4
   m4/pthread_sigmask.m4
-  m4/putenv.m4
   m4/readlink.m4
   m4/readlinkat.m4
   m4/regex.m4
diff --git a/m4/putenv.m4 b/m4/putenv.m4
deleted file mode 100644
index e38f8c56940..00000000000
--- a/m4/putenv.m4
+++ /dev/null
@@ -1,60 +0,0 @@
-# putenv.m4 serial 24
-dnl Copyright (C) 2002-2020 Free Software Foundation, Inc.
-dnl This file is free software; the Free Software Foundation
-dnl gives unlimited permission to copy and/or distribute it,
-dnl with or without modifications, as long as this notice is preserved.
-
-dnl From Jim Meyering.
-dnl
-dnl Check whether putenv ("FOO") removes FOO from the environment.
-dnl The putenv in libc on at least SunOS 4.1.4 does *not* do that.
-
-AC_DEFUN([gl_FUNC_PUTENV],
-[
-  AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
-  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
-  AC_CACHE_CHECK([for putenv compatible with GNU and SVID],
-   [gl_cv_func_svid_putenv],
-   [AC_RUN_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT],[[
-    /* Put it in env.  */
-    if (putenv ("CONFTEST_putenv=val"))
-      return 1;
-
-    /* Try to remove it.  */
-    if (putenv ("CONFTEST_putenv"))
-      return 2;
-
-    /* Make sure it was deleted.  */
-    if (getenv ("CONFTEST_putenv") != 0)
-      return 3;
-
-    return 0;
-              ]])],
-             gl_cv_func_svid_putenv=yes,
-             gl_cv_func_svid_putenv=no,
-             dnl When crosscompiling, assume putenv is broken.
-             [case "$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, obey --enable-cross-guesses.
-                *)             gl_cv_func_svid_putenv="$gl_cross_guess_normal" ;;
-              esac
-             ])
-   ])
-  case "$gl_cv_func_svid_putenv" in
-    *yes) ;;
-    *)
-      REPLACE_PUTENV=1
-      ;;
-  esac
-])
-
-# Prerequisites of lib/putenv.c.
-AC_DEFUN([gl_PREREQ_PUTENV],
-[
-  AC_CHECK_DECLS([_putenv])
-])