diff --git a/flang/docs/OpenACC.md b/flang/docs/OpenACC.md
index 87f30ccd953b6..6d384f93ae216 100644
--- a/flang/docs/OpenACC.md
+++ b/flang/docs/OpenACC.md
@@ -27,6 +27,9 @@ local:
 * `!$acc cache` directive accepts scalar variable.
 * The `!$acc declare` directive accepts assumed size array arguments for 
   `deviceptr` and `present` clauses.
+* The OpenACC specification disallows a variable appearing multiple times in
+  clauses of `!$acc declare` directives for a function, subroutine, program,
+  or module, but it is allowed with a warning when same clause is used.
 
 ## Remarks about incompatibilities with other implementations
 * Array element references in the data clauses are equivalent to array sections