[Bug c++/101695] calling incorrect destructor of same-name class in anonymous namespaces in separate translation units

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101695

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
  Attachment #51268|0                           |1
        is obsolete|                            |

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
Created attachment 51269
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=51269&action=edit
Tar file with reproducer

Slightly further reduced.

The bug is the visibility of this symbol:

0000000000000000 W
_ZN8DelegateIFvPvEE4bindI11MemoryArenaXadL_ZNS4_7destroyIN12_GLOBAL__N_16TesterEEEvS0_EEEERS2_PT_


That should have internal linkage. Because both aaa.o and bbb.o contain that as
a weak symbol, the linker merges them and only keeps the first one, which runs
the destroy<{aaa.cpp anonymous namespace}::Tester> specialization, which casts
the void* to that type and so deletes it as the wrong type, which runs the
wrong destructor, and decrements the wrong counter.