[Bug lto/91273] New: [7/8/9/10 Regression] ICE in warn_types_mismatch at ipa-devirt.c:995

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91273

            Bug ID: 91273
           Summary: [7/8/9/10 Regression] ICE in warn_types_mismatch at
                    ipa-devirt.c:995
           Product: gcc
           Version: 9.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: lto
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marxin at gcc dot gnu.org
                CC: marxin at gcc dot gnu.org
  Target Milestone: ---

I see following ICE from r224248:

$ cat 1.ii
cat 1.ii
extern "C" {
struct {
} ltregul_;
}

$ cat 2.F
        common /ltregul/ zeroeps
        end         

$ g++ 1.ii 2.F -flto -O2 
2.F:1:3: warning: type of ‘ltregul’ does not match original declaration
[-Wlto-type-mismatch]
    1 |  common /ltregul/ zeroeps
      |   ^
lto1: internal compiler error: in warn_types_mismatch, at ipa-devirt.c:995
0x626616 warn_types_mismatch(tree_node*, tree_node*, unsigned int, unsigned
int)
        /home/marxin/Programming/gcc/gcc/ipa-devirt.c:995
0x7e536c lto_symtab_merge_decls_2
        /home/marxin/Programming/gcc/gcc/lto/lto-symtab.c:722
0x7e536c lto_symtab_merge_decls_1
        /home/marxin/Programming/gcc/gcc/lto/lto-symtab.c:861
0x7e536c lto_symtab_merge_decls()
        /home/marxin/Programming/gcc/gcc/lto/lto-symtab.c:887
0x7f0f28 read_cgraph_and_symbols(unsigned int, char const**)
        /home/marxin/Programming/gcc/gcc/lto/lto-common.c:2839
0x7d7702 lto_main()
        /home/marxin/Programming/gcc/gcc/lto/lto.c:616