[flang-commits] [flang] [flang][docs] Add an FAQ about an executable stack (PR #171241)

[Tarun Prabhu via flang-commits]

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@@ -0,0 +1,52 @@
+<!--===- docs/FAQ.md
+
+   Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+   See https://llvm.org/LICENSE.txt for license information.
+   SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+-->
+
+# Frequently Asked Questions (FAQ)
+
+```{contents}
+---
+local:
+---
+```
+
+## Driver
+
+### Why do I get a warning or an error about an executable stack?
+
+This occurs because Flang's implementation of pointers to internal procedures requires an executable stack.
+
+An internal procedure has a "host scope", which is the scope surrounding it.
+It can access variables in the host scope.
+When an internal procedure is referenced from outside its host scope (for example, via a procedure pointer), the implementation must ensure that it can still access variables from that host scope.
----------------
tarunprabhu wrote:

```suggestion
When an internal procedure is referenced from outside its host scope (for example, via a procedure pointer), the implementation must ensure that it can still access variables from the host scope.
```

https://github.com/llvm/llvm-project/pull/171241