[Bug fortran/105170] New: Invalid finalization in intrinsic assignment

[baradi09 at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105170

            Bug ID: 105170
           Summary: Invalid finalization in intrinsic assignment
           Product: gcc
           Version: 11.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: fortran
          Assignee: unassigned at gcc dot gnu.org
          Reporter: baradi09 at gmail dot com
  Target Milestone: ---

Created attachment 52754
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=52754&action=edit
Minimal working example demonstrating the bug

I have a derived type (TWrapper), which has a component with defined
assignment. The containing derived type itself has no defined assignment. Upon
an assignment between two TWrapper instances, a copy of the RHS seems to get
finalized.

The attached MWE demonstrates the problem.

Expected output (as delivered by current Intel and NAG compilers):

RefCounter_final, id:0
TRefCounter_init: id:42
-> Assignment wrapper2 = wrapper
TRefCounter_final, id:0
TRefCounter_final, id:0
TRefCounter_assign: this%id, other%id: 0 42

GFortran output:

TRefCounter_final, id:0
TRefCounter_init: id:42
-> Assignment wrapper2 = wrapper
TRefCounter_final, id:42
TRefCounter_assign: this%id, other%id: 0 42

One finalization seems to be missing. Additionally, the finalized instance
seems to be a copy of the RHS. (A copy, because after the finalization, the RHS
still seems to have kept its id-value...)