Merged current trunk to branch.
diff --git a/libgomp/libgomp-plugin.h b/libgomp/libgomp-plugin.h
index 64f138d..cf24a2b 100644
--- a/libgomp/libgomp-plugin.h
+++ b/libgomp/libgomp-plugin.h
@@ -1,6 +1,6 @@
 /* The libgomp plugin API.
 
-   Copyright (C) 2014-2020 Free Software Foundation, Inc.
+   Copyright (C) 2014-2021 Free Software Foundation, Inc.
 
    Contributed by Mentor Embedded.
 
@@ -102,6 +102,12 @@
   uintptr_t end;
 };
 
+/* This symbol is to name a target side variable that holds the designated
+   'device number' of the target device. The symbol needs to be available to
+   libgomp code and the offload plugin (which in the latter case must be
+   stringified).  */
+#define GOMP_DEVICE_NUM_VAR __gomp_device_num
+
 /* Miscellaneous functions.  */
 extern void *GOMP_PLUGIN_malloc (size_t) __attribute__ ((malloc));
 extern void *GOMP_PLUGIN_malloc_cleared (size_t) __attribute__ ((malloc));