# HG changeset patch
# User Bruno Haible <bruno@clisp.org>
# Date 1307277176 -7200
# Node ID 355e7137b2def81c304337e18f63a357ede270ee
# Parent  0d4d726862cad8b7a9e1378a8ffea8e5097d6d14
unsetenv: Avoid gcc warning.

* lib/unsetenv.c (unsetenv): Provide declaration if system lacks it.

diff --git a/ChangeLog b/ChangeLog
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2011-06-05  Bruno Haible  <bruno@clisp.org>
+
+	unsetenv: Avoid gcc warning.
+	* lib/unsetenv.c (unsetenv): Provide declaration if system lacks it.
+
 2011-06-05  Bruno Haible  <bruno@clisp.org>
 
 	setenv: Avoid gcc warning.
diff --git a/lib/unsetenv.c b/lib/unsetenv.c
--- a/lib/unsetenv.c
+++ b/lib/unsetenv.c
@@ -97,6 +97,13 @@
 #else /* HAVE_UNSETENV */
 
 # undef unsetenv
+# if !HAVE_DECL_UNSETENV
+#  if VOID_UNSETENV
+extern void unsetenv (const char *);
+#  else
+extern int unsetenv (const char *);
+#  endif
+# endif
 
 /* Call the underlying unsetenv, in case there is hidden bookkeeping
    that needs updating beyond just modifying environ.  */