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

[Yusuke MINATO via flang-commits]

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@@ -0,0 +1,47 @@
+<!--===- 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
+
+-->
+
+<!-- TODO: remove this after adding this page to ToC -->
+```{eval-rst}
+:orphan:
+```
+
+# Frequently Asked Questions (FAQ)
+
+```{contents}
+---
+local:
+---
+```
+
+## Driver
+
+### Why do I get a warning or error about an executable stack?
----------------
yus3710-fj wrote:

> Will the choice of linker determine whether a user sees a warning or an error? Just curious

The GNU Linker (`ld`) treats warnings as errors if `--fatal-warnings` is specified.

```console
$ flang src.f90 -Wl,--fatal-warnings
/path/to/ld: warning: src.o: requires executable stack (because the .note.GNU-stack section is executable)
flang-22: error: linker command failed with exit code 1 (use -v to see invocation)
```

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