Basic response file support

Here we introduce support into our command-line parsing infrastructure
and driver for handling gnu-style response file arguments,
typically used to work around platform command-line length limitations.

Fixes #16476.

2 files changed, 14 insertions, 0 deletions

diff --git a/docs/users_guide/9.4.1-notes.rst b/docs/users_guide/9.4.1-notes.rst
index cea17cac60..0273859173 100644
--- a/docs/users_guide/9.4.1-notes.rst
+++ b/docs/users_guide/9.4.1-notes.rst
@@ -60,6 +60,9 @@ Language
 Compiler
 ~~~~~~~~
 
+- The compiler now accepts arguments via GNU-style response files
+  (:ghc-ticket:`16476`).
+
 - New :ghc-flag:`-Wredundant-strictness-flags` that checks for strictness flags
   (``!``) applied to unlifted types, which are always strict.
 
diff --git a/docs/users_guide/using.rst b/docs/users_guide/using.rst
index 628dfab0f3..ee61a89ce1 100644
--- a/docs/users_guide/using.rst
+++ b/docs/users_guide/using.rst
@@ -85,6 +85,17 @@ all files; you cannot, for example, invoke
 ``ghc -c -O1 Foo.hs -O2 Bar.hs`` to apply different optimisation levels
 to the files ``Foo.hs`` and ``Bar.hs``.
 
+In addition to passing arguments via the command-line, arguments can be passed
+via GNU-style response files. For instance,
+
+.. code-block:: bash
+
+    $ cat response-file
+    -O1
+    Hello.hs
+    -o Hello
+    $ ghc @response-file
+
 .. note::
 
     .. index::