[Bug lto/65475] [5 Regression] ICE in odr_vtable_hasher::equal (Segmentation fault)

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65475

--- Comment #4 from Martin Liška <marxin at gcc dot gnu.org> ---
Unfortunately, there is another problem with applied patch:

$ cat 1.ii
namespace std {
class exception {};
class runtime_error : exception {
  virtual char m_fn1();
} a;
}

$ cat 2.ii
namespace std {
class exception {
  virtual char m_fn1();
};
class runtime_error : exception {
} a;
}

$ g++ 1.ii 2.ii -flto -O1
/home/marxin/Programming/bin/gcc/bin/ld: error: /tmp/cc7v39VO.o: multiple
definition of 'std::a'
/home/marxin/Programming/bin/gcc/bin/ld: /tmp/ccJ8pPM4.o: previous definition
here
2.ii:2:7: warning: type ‘struct exception’ violates one definition rule [-Wodr]
 class exception {
       ^
1.ii:2:7: note: a type with different virtual table pointers is defined in
another translation unit
 class exception {};
       ^
2.ii:2:7: warning: type ‘struct exception’ violates one definition rule [-Wodr]
 class exception {
       ^
1.ii:2:7: note: a type with different bases is defined in another translation
unit
 class exception {};
       ^
1.ii:3:7: warning: type ‘struct runtime_error’ violates one definition rule
[-Wodr]
 class runtime_error : exception {
       ^
2.ii:5:7: note: a type with different virtual table pointers is defined in
another translation unit
 class runtime_error : exception {
       ^
lto1: internal compiler error: in add_type_duplicate, at ipa-devirt.c:1575
0x77c43c add_type_duplicate
    ../../gcc/ipa-devirt.c:1573
0x77c43c get_odr_type(tree_node*, bool)
    ../../gcc/ipa-devirt.c:1772
0x77d25c register_odr_type(tree_node*)
    ../../gcc/ipa-devirt.c:1848
0x5b43d6 lto_read_decls
    ../../gcc/lto/lto.c:1946
0x5b4d7b lto_file_finalize
    ../../gcc/lto/lto.c:2236
0x5b4d7b lto_create_files_from_ids
    ../../gcc/lto/lto.c:2246
0x5b4d7b lto_file_read
    ../../gcc/lto/lto.c:2287
0x5b4d7b read_cgraph_and_symbols
    ../../gcc/lto/lto.c:2992
0x5b4d7b lto_main()
    ../../gcc/lto/lto.c:3462


Thanks,
Martin