3 files changed, 47 insertions, 7 deletions
diff --git a/include/errno.h b/include/errno.h
index 35f705100e..9969b1f519 100644
--- a/include/errno.h
+++ b/include/errno.h
@@ -1,13 +1,20 @@
+#ifndef _ERRNO_H
+
 #include <stdlib/errno.h>
 
 #ifdef _ERRNO_H
 
-#if USE_TLS && HAVE___THREAD
-# undef errno
+# include <tls.h>		/* Defines USE_TLS.  */
+
+# if USE_TLS && HAVE___THREAD
+#  undef  errno
+#  define errno errno		/* For #ifndef errno tests.  */
 extern __thread int errno;
-# define __set_errno(val) (errno = (val))
-#else
-# define __set_errno(val) (*__errno_location ()) = (val)
-#endif
+#  define __set_errno(val) (errno = (val))
+# else
+#  define __set_errno(val) (*__errno_location ()) = (val)
+# endif
+
+#endif /* _ERRNO_H */
 
-#endif
+#endif /* ! _ERRNO_H */
diff --git a/include/netdb.h b/include/netdb.h
index 0a97c01a3e..1f2ab032e2 100644
--- a/include/netdb.h
+++ b/include/netdb.h
@@ -1,6 +1,26 @@
 #ifndef	_NETDB_H
 #include <resolv/netdb.h>
 
+/* Macros for accessing h_errno from inside libc.  */
+# ifdef _LIBC_REENTRANT
+#  include <tls.h>
+#  if USE_TLS && HAVE___THREAD
+#   undef  h_errno
+#   define h_errno h_errno	/* For #ifndef h_errno tests.  */
+extern __thread int h_errno;
+#   define __set_h_errno(x)	(h_errno = (x))
+#  else
+static inline int
+__set_h_errno (int __err)
+{
+  return *__h_errno_location () = __err;
+}
+#  endif
+# else
+#  undef  h_errno
+#  define __set_h_errno(x) (h_errno = (x))
+# endif	/* _LIBC_REENTRANT */
+
 /* Document internal interfaces.  */
 extern int __gethostent_r (struct hostent *__restrict __result_buf,
 			   char *__restrict __buf, size_t __buflen,
diff --git a/include/resolv.h b/include/resolv.h
index d4a531f244..6d7008b81a 100644
--- a/include/resolv.h
+++ b/include/resolv.h
@@ -11,6 +11,19 @@
 #include <resolv/resolv.h>
 
 #ifdef _RESOLV_H_
+
+# ifdef _LIBC_REENTRANT
+#  include <tls.h>
+#  if USE_TLS && HAVE___THREAD
+#   undef _res
+extern __thread struct __res_state _res;
+#  endif
+# else
+#  ifndef __BIND_NOSTATIC
+extern struct __res_state _res;
+#  endif
+# endif
+
 /* Now define the internal interfaces.  */
 extern int __res_vinit (res_state, int);
 extern void _sethtent (int);