[gcc r16-1464] libstdc++: Improve documentation on copyright notices in new tests

[Jonathan Wakely]

https://gcc.gnu.org/g:905593af060a0c001d6e8caadf831243085c1db7

commit r16-1464-g905593af060a0c001d6e8caadf831243085c1db7
Author: Jonathan Wakely <jwakely@redhat.com>
Date:   Tue Jun 10 09:56:05 2025 +0100

    libstdc++: Improve documentation on copyright notices in new tests
    
    Clarify that FSF copyright notices in tests are incorrect for
    contributions under DCO terms. Clarify the sentence about copying
    existing tests to clarify that it is only referring to copying the code
    in the test file, rather than just copying an existing file as a
    template for a new test.
    
    libstdc++-v3/ChangeLog:
    
            * doc/xml/manual/test.xml: Improve discussion of copyright
            notices in new test cases.
            * doc/html/manual/test.html: Regenerate.

Diff:
---
 libstdc++-v3/doc/html/manual/test.html | 11 ++++++++---
 libstdc++-v3/doc/xml/manual/test.xml   | 12 +++++++++---
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/libstdc++-v3/doc/html/manual/test.html b/libstdc++-v3/doc/html/manual/test.html
index f6776f2e0415..497ee1ad36e5 100644
--- a/libstdc++-v3/doc/html/manual/test.html
+++ b/libstdc++-v3/doc/html/manual/test.html
@@ -389,10 +389,15 @@ cat 27_io/objects/char/3_xin.in | a.out</pre></dd><dt><span class="term"><code c
     We no longer require that, because most tests are uninteresting
     and contain no "original authorship", and so would not be protected
     by copyright anyway.
-    If you do want to add the FSF copyright notice and GPL licence text,
+    Adding the FSF copyright notice to new tests is incorrect unless you
+    (or your employer) have a copyright assignment on file with the FSF,
+    or if the test contains code copied from another test under FSF copyright.
+    In particular, new tests that contain original code are not copyright FSF
+    if contributed under the <a class="link" href="https://gcc.gnu.org/dco.html" target="_top">DCO</a> terms.
+    If new tests do add the FSF copyright notice and GPL licence text,
     then the first copyright year should correspond to the date
-    the file was checked in to version control. If a test is copied from
-    an existing file it should retain the copyright years from the
+    the file was checked in to version control. If the test code is copied
+    from an existing file it should retain the copyright years from the
     original file.
    </p><p>
      The DejaGnu instructions say to always return <code class="literal">0</code>
diff --git a/libstdc++-v3/doc/xml/manual/test.xml b/libstdc++-v3/doc/xml/manual/test.xml
index f0139dfd7937..df49f56b0d03 100644
--- a/libstdc++-v3/doc/xml/manual/test.xml
+++ b/libstdc++-v3/doc/xml/manual/test.xml
@@ -650,10 +650,16 @@ cat 27_io/objects/char/3_xin.in | a.out</programlisting>
     We no longer require that, because most tests are uninteresting
     and contain no "original authorship", and so would not be protected
     by copyright anyway.
-    If you do want to add the FSF copyright notice and GPL licence text,
+    Adding the FSF copyright notice to new tests is incorrect unless you
+    (or your employer) have a copyright assignment on file with the FSF,
+    or if the test contains code copied from another test under FSF copyright.
+    In particular, new tests that contain original code are not copyright FSF
+    if contributed under the <link xmlns:xlink="http://www.w3.org/1999/xlink"
+      xlink:href="https://gcc.gnu.org/dco.html">DCO</link> terms.
+    If new tests do add the FSF copyright notice and GPL licence text,
     then the first copyright year should correspond to the date
-    the file was checked in to version control. If a test is copied from
-    an existing file it should retain the copyright years from the
+    the file was checked in to version control. If the test code is copied
+    from an existing file it should retain the copyright years from the
     original file.
    </para>