[PATCH v3] secilc/docs: document expandtypeattribute

[Dominick Grift <dominick.grift@xxxxxxxxxxx>]

This was added for Androids Treble in 2017.

I was unsure whether this belongs in type_statements or in conditional_statements.

Signed-off-by: Dominick Grift <dominick.grift@xxxxxxxxxxx>
---
v2: overriden is overridden
v3: add link to README.md

 secilc/docs/README.md              |  1 +
 secilc/docs/cil_type_statements.md | 38 ++++++++++++++++++++++++++++++
 2 files changed, 39 insertions(+)

diff --git a/secilc/docs/README.md b/secilc/docs/README.md
index 3f1838e6..efab2a71 100644
--- a/secilc/docs/README.md
+++ b/secilc/docs/README.md
@@ -126,6 +126,7 @@ CIL (Common Intermediate Language)
   * [typealiasactual](cil_type_statements.md#typealiasactual)
   * [typeattribute](cil_type_statements.md#typeattribute)
   * [typeattributeset](cil_type_statements.md#typeattributeset)
+  * [expandtypeattribute](cil_type_statements.md#expandtypeattribute)
   * [typebounds](cil_type_statements.md#typebounds)
   * [typechange](cil_type_statements.md#typechange)
   * [typemember](cil_type_statements.md#typemember)
diff --git a/secilc/docs/cil_type_statements.md b/secilc/docs/cil_type_statements.md
index f9dd3a76..f819b3c6 100644
--- a/secilc/docs/cil_type_statements.md
+++ b/secilc/docs/cil_type_statements.md
@@ -213,6 +213,44 @@ This example is equivalent to `{ domain -kernel.process -ueventd.process -init.p
         )
     )
 
+expandtypeattribute
+-------------------
+
+Allows expansion compiler defaults for one or more previously declared [`typeattribute`](cil_type_statements.md#typeattribute) identifiers to be overridden.
+
+**Statement definition:**
+
+    (expandtypeattribute typeattribute_id true|false)
+
+**Where:**
+
+<table>
+<colgroup>
+<col width="25%" />
+<col width="75%" />
+</colgroup>
+<tbody>
+<tr class="odd">
+<td align="left"><p><code>expandtypeattribute</code></p></td>
+<td align="left"><p>The <code>expandtypeattribute</code> keyword.</p></td>
+</tr>
+<tr class="even">
+<td align="left"><p><code>typeattribute_id</code></p></td>
+<td align="left"><p>One or more previously declared <code>typeattribute</code> identifiers.</p></td>
+</tr>
+<tr class="odd">
+<td align="left"><p><code>true | false</code></p></td>
+<td align="left"><p>Either true or false.</p></td>
+</tr>
+</tbody>
+</table>
+
+**Example:**
+
+This example will use the expandtypeattribute statement to forcibly expand a previously declared `domain` type attribute.
+
+    (expandtypeattribute domain true)
+
 typebounds
 ----------
 
-- 
2.28.0.rc1