gnulib-tool --import environ; rely on gnulib for environ definitions

* libguile/posix.c:
* libguile/stime.c: Remove environ definition, gnulib provides it now.

lib/Makefile.am

@@ -9,7 +9,7 @@
 # the same distribution terms as the rest of that program.
 #
 # Generated by gnulib-tool.
-# Reproduce by: gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --lgpl --libtool --macro-prefix=gl --no-vc-files alloca-opt autobuild count-one-bits extensions flock fpieee full-read full-write lib-symbol-visibility putenv stdlib strcase strftime
+# Reproduce by: gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --lgpl --libtool --macro-prefix=gl --no-vc-files alloca-opt autobuild count-one-bits environ extensions flock fpieee full-read full-write lib-symbol-visibility putenv stdlib strcase strftime
 
 AUTOMAKE_OPTIONS = 1.5 gnits
 

libguile/posix.c

@@ -101,8 +101,6 @@ extern char *ttyname();
 
 #include <signal.h>
 
-extern char ** environ;
-
 #ifdef HAVE_GRP_H
 #include <grp.h>
 #endif
@@ -140,10 +138,6 @@ extern char ** environ;
 
 #include <sys/file.h>     /* from Gnulib */
 
-#if HAVE_CRT_EXTERNS_H
-#include <crt_externs.h>  /* for Darwin _NSGetEnviron */
-#endif
-
 /* Some Unix systems don't define these.  CPP hair is dangerous, but
    this seems safe enough... */
 #ifndef R_OK
@@ -196,13 +190,6 @@ int sethostname (char *name, size_t namelen);
 
 
 
-/* On Apple Darwin in a shared library there's no "environ" to access
-   directly, instead the address of that variable must be obtained with
-   _NSGetEnviron().  */
-#if HAVE__NSGETENVIRON && defined (PIC)
-#define environ (*_NSGetEnviron())
-#endif
-
 
 
 /* Two often used patterns

libguile/stime.c

@@ -77,10 +77,6 @@
 # include <sys/timeb.h>
 #endif
 
-#if HAVE_CRT_EXTERNS_H
-#include <crt_externs.h>  /* for Darwin _NSGetEnviron */
-#endif
-
 #ifndef tzname /* For SGI.  */
 extern char *tzname[]; /* RS6000 and others reject char **tzname.  */
 #endif
@@ -98,15 +94,6 @@ extern char *strptime ();
 # define timet long
 #endif
 
-extern char ** environ;
-
-/* On Apple Darwin in a shared library there's no "environ" to access
-   directly, instead the address of that variable must be obtained with
-   _NSGetEnviron().  */
-#if HAVE__NSGETENVIRON && defined (PIC)
-#define environ (*_NSGetEnviron())
-#endif
-
 
 #ifdef HAVE_TIMES
 static

m4/environ.m4

@@ -0,0 +1,36 @@
+# environ.m4 serial 2
+dnl Copyright (C) 2001-2004, 2006-2009 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.
+
+AC_DEFUN([gl_ENVIRON],
+[
+  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+  dnl Persuade glibc <unistd.h> to declare environ.
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+  gt_CHECK_VAR_DECL([#include <unistd.h>], environ)
+  if test $gt_cv_var_environ_declaration != yes; then
+    HAVE_DECL_ENVIRON=0
+  fi
+])
+
+# Check if a variable is properly declared.
+# gt_CHECK_VAR_DECL(includes,variable)
+AC_DEFUN([gt_CHECK_VAR_DECL],
+[
+  define([gt_cv_var], [gt_cv_var_]$2[_declaration])
+  AC_MSG_CHECKING([if $2 is properly declared])
+  AC_CACHE_VAL([gt_cv_var], [
+    AC_TRY_COMPILE([$1
+      extern struct { int foo; } $2;],
+      [$2.foo = 1;],
+      gt_cv_var=no,
+      gt_cv_var=yes)])
+  AC_MSG_RESULT([$gt_cv_var])
+  if test $gt_cv_var = yes; then
+    AC_DEFINE([HAVE_]translit($2, [a-z], [A-Z])[_DECL], 1,
+              [Define if you have the declaration of $2.])
+  fi
+  undefine([gt_cv_var])
+])

m4/gnulib-cache.m4

@@ -15,7 +15,7 @@
 
 
 # Specification in the form of a command-line invocation:
-#   gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --lgpl --libtool --macro-prefix=gl --no-vc-files alloca-opt autobuild count-one-bits extensions flock fpieee full-read full-write lib-symbol-visibility putenv stdlib strcase strftime
+#   gnulib-tool --import --dir=. --lib=libgnu --source-base=lib --m4-base=m4 --doc-base=doc --tests-base=tests --aux-dir=build-aux --lgpl --libtool --macro-prefix=gl --no-vc-files alloca-opt autobuild count-one-bits environ extensions flock fpieee full-read full-write lib-symbol-visibility putenv stdlib strcase strftime
 
 # Specification in the form of a few gnulib-tool.m4 macro invocations:
 gl_LOCAL_DIR([])
@@ -23,6 +23,7 @@ gl_MODULES([
   alloca-opt
   autobuild
   count-one-bits
+  environ
   extensions
   flock
   fpieee

m4/gnulib-comp.m4

@@ -45,6 +45,8 @@ AC_DEFUN([gl_INIT],
   gl_source_base='lib'
   gl_FUNC_ALLOCA
   gl_COUNT_ONE_BITS
+  gl_ENVIRON
+  gl_UNISTD_MODULE_INDICATOR([environ])
   gl_FUNC_FLOCK
   gl_HEADER_SYS_FILE_MODULE_INDICATOR([flock])
   gl_INLINE
@@ -251,6 +253,7 @@ AC_DEFUN([gl_FILE_LIST], [
   m4/autobuild.m4
   m4/codeset.m4
   m4/count-one-bits.m4
+  m4/environ.m4
   m4/extensions.m4
   m4/flock.m4
   m4/fpieee.m4