gnu /
gcc /
809c5d7486f91d59e798e0c70ac887f837039ece c++: C++17/20 class layout divergence [PR120012]
C++20 made a class with only explicitly defaulted constructors no longer
aggregate, and this wrongly affected whether the class is considered "POD
for layout purposes" under the ABI.
Conveniently, we already have check_non_pod_aggregate to diagnose cases
where this makes a difference, due to PR103681 around a C++14 aggregate
change.
This backport is the same code change as the trunk version, but since
-fabi-version=21 cannot be selected, the fix is not available, only the
warning, so the first testcase is different.
PR c++/120012
gcc/cp/ChangeLog:
* cp-tree.h (struct lang_type): Add non_aggregate_pod.
(CLASSTYPE_NON_AGGREGATE_POD): New.
* class.cc (check_bases_and_members): Set it.
(check_non_pod_aggregate): Diagnose it.
gcc/testsuite/ChangeLog:
* g++.dg/abi/base-defaulted1.C: New test.
* g++.dg/abi/base-defaulted1a.C: New test.
(cherry picked from commit e6e3b0772ed40cc65a544bbe744ece62d8b9713e)
4 files changed
