Mimic gcc behaviour with regard to response files.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62688 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/docs/CommandGuide/llvmc.pod b/docs/CommandGuide/llvmc.pod
index 17d85d7..53eecaf 100644
--- a/docs/CommandGuide/llvmc.pod
+++ b/docs/CommandGuide/llvmc.pod
@@ -78,8 +78,24 @@
Print version information and exit.
+=item B<@>I<file>
+
+Read command-line options from I<file>. The options read are inserted
+in place of the original @I<file> option. If I<file> does not exist, or
+cannot be read, then the option will be treated literally, and not
+removed.
+
+Options in I<file> are separated by whitespace. A whitespace character
+may be included in an option by surrounding the entire option in
+either single or double quotes. Any character (including a backslash)
+may be included by prefixing the character to be included with a
+backslash. The file may itself contain additional @I<file> options;
+any such options will be processed recursively.
+
+
=back
+
=head2 Control Options
By default, LLVMC is built with some standard configuration libraries