http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50919
Bug #: 50919 Summary: [OOP] Don't use vtable for NON_OVERRIDABLE TBP Classification: Unclassified Product: gcc Version: 4.7.0 Status: UNCONFIRMED Keywords: missed-optimization Severity: normal Priority: P3 Component: fortran AssignedTo: unassig...@gcc.gnu.org ReportedBy: bur...@gcc.gnu.org CC: ja...@gcc.gnu.org Current, gfortran uses always a vtable for type-bound procedures. However, a vtable only makes sense if the type-bound procedure can be overridden (C++: if it is "virtual"). Expected: a) gfortran call the procedure directly, which allows for inlining and avoids the pointer dereference. b) When the ABI is changed, the procedure is no longer added to the vtable. Hence, it should be added as item to http://gcc.gnu.org/wiki/LibgfortranAbiCleanup Test case. The dump shows the following rather than a simple "test ()": callit (struct __class_m_T & restrict x) { x->_vptr->test (); module m type t contains procedure, nopass, NON_OVERRIDABLE :: test end type t contains subroutine test() print *, "t's test" end subroutine test subroutine callit(x) class(t) :: x call x%test() end subroutine end module m tob@archimedes:/dev/shm> less poly.f90.* tob@archimedes:/dev/shm> cat poly.f90 module m type t contains procedure, nopass, NON_OVERRIDABLE :: test end type t contains subroutine test() print *, "t's test" end subroutine test subroutine callit(x) class(t) :: x call x%test() end subroutine end module m