diff --git a/docs/devel/style.rst b/docs/devel/style.rst
index 3cfcdeb9cd..2f68b50079 100644
--- a/docs/devel/style.rst
+++ b/docs/devel/style.rst
@@ -204,7 +204,14 @@ Declarations
 
 Mixed declarations (interleaving statements and declarations within
 blocks) are generally not allowed; declarations should be at the beginning
-of blocks.
+of blocks. To avoid accidental re-use it is permissible to declare
+loop variables inside for loops:
+
+.. code-block:: c
+
+    for (int i = 0; i < ARRAY_SIZE(thing); i++) {
+        /* do something loopy */
+    }
 
 Every now and then, an exception is made for declarations inside a
 #ifdef or #ifndef block: if the code looks nicer, such declarations can