https://gcc.gnu.org/bugzilla/show_bug.cgi?id=120098
--- Comment #31 from GCC Commits <cvs-commit at gcc dot gnu.org> --- The releases/gcc-15 branch has been updated by Richard Biener <[email protected]>: https://gcc.gnu.org/g:522e0c0bdabfa39f2c3bfc3f7a3d3c2b60b62381 commit r15-11240-g522e0c0bdabfa39f2c3bfc3f7a3d3c2b60b62381 Author: Jan Hubicka <[email protected]> Date: Fri Apr 17 17:34:35 2026 +0200 Fix handling of anonymous type vtables in ipa-devirt Solve first problem discussed in PR120098 where modified devirt-23 testcase leads to wrong code. The testcase triggers situation whre anonymous type MultiTermDocs is derived by C. When we look for possible polymorphic call targets, we special case anonymous type and check if they have been instantiated by looking if their virtual table is used at all. In this case it is not, however C has construction vtable which refers to MultiTermDocs's virtual function. Since we have no easy way to go from a type to all construction vtables of its derived types, this is fixed by adding a walk of variables and noting them. Walk is triggered lazilly only when such anonymous types exists. gcc/ChangeLog: PR ipa/120098 * ipa-devirt.cc (odr_type_p): Add no_derived_construction_vtables (odr_types_ptr): Move ahead in file. (odr_types): Move ahead in file. (anonymous_construction_vtable_p): New function. (mark_derived_construction_vtables): New function. (construction_vtable_hook): New function. (type_possibly_instantiated_p): Watch for construction vtables. gcc/testsuite/ChangeLog: PR ipa/120098 * g++.dg/torture/pr120098.C: New test. (cherry picked from commit 5e492f27e44c052237a7296d7fb754bae5755982)
