The warning reported in PR 98835 is a true positive but there was no test for this aspect of it. I have added one on the attached diff.
Martin
commit c2f8e378d64f65645e5f9c41a8221ca102c71208 Author: Martin Sebor <mse...@redhat.com> Date: Mon Feb 1 08:42:58 2021 -0700 Verify a warning for a class with a ref-qualified assignment (PR c++/98835). gcc/testsuite/ChangeLog: PR c++/98835 * g++.dg/Wclass-memaccess-6.C: New test. diff --git a/gcc/testsuite/g++.dg/Wclass-memaccess-6.C b/gcc/testsuite/g++.dg/Wclass-memaccess-6.C new file mode 100644 index 00000000000..7f6fe03a939 --- /dev/null +++ b/gcc/testsuite/g++.dg/Wclass-memaccess-6.C @@ -0,0 +1,18 @@ +/* PR c++/98835 - -Wclass-memaccess with class with ref-qualified + copy-assignment operator + { dg-do compile { target { c++11 } } } + { dg-options "-Wall" } */ + +struct Bad +{ + Bad* operator& () { return this; } + Bad & operator=(Bad const &) & = default; +}; + +void test () +{ + static_assert (__has_trivial_copy (Bad)); + + // T () = T (); // error + __builtin_memcpy (&Bad (), &Bad (), sizeof (Bad)); // { dg-warning "\\\[-Wclass-memaccess" } +}