[Bug ipa/91831] New: [10 Regression] ICE in expand_expr_real_1, at expr.c:10062 after r275982

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91831

            Bug ID: 91831
           Summary: [10 Regression] ICE in expand_expr_real_1, at
                    expr.c:10062 after r275982
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: ipa
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marxin at gcc dot gnu.org
                CC: marxin at gcc dot gnu.org, mjambor at suse dot cz
  Target Milestone: ---

After the revision I see the following issue:

$ cat ice.C
struct A {
  virtual void m_fn1();
};
struct B {
  virtual void *m_fn2(int, int) = 0;
};
struct C : A, B {
  void *m_fn2(int, int) { return this; }
};
void *fn1(B &p1) { return p1.m_fn2(0, 0); }

int main() {
  C c;
  fn1(c);
  return 0;
}

$ gcc ice.C -O2 --param uninlined-thunk-insns=1000 -c
during RTL pass: expand
ice.C: In function ‘_ZThn8_N1C5m_fn2Eii.artificial_thunk.0’:
ice.C:8:9: internal compiler error: in expand_expr_real_1, at expr.c:10062
    8 |   void *m_fn2(int, int) { return this; }
      |         ^~~~~
0x6f5e79 expand_expr_real_1(tree_node*, rtx_def*, machine_mode,
expand_modifier, rtx_def**, bool)
        /home/marxin/Programming/gcc/gcc/expr.c:10062
0xcaace4 expand_expr
        /home/marxin/Programming/gcc/gcc/expr.h:281
0xcaace4 expand_operands(tree_node*, tree_node*, rtx_def*, rtx_def**,
rtx_def**, expand_modifier)
        /home/marxin/Programming/gcc/gcc/expr.c:7887
0xcb2627 expand_expr_real_2(separate_ops*, rtx_def*, machine_mode,
expand_modifier)
        /home/marxin/Programming/gcc/gcc/expr.c:8783
0xca1c41 expand_expr_real_1(tree_node*, rtx_def*, machine_mode,
expand_modifier, rtx_def**, bool)
        /home/marxin/Programming/gcc/gcc/expr.c:9993
0xb88fed expand_expr
        /home/marxin/Programming/gcc/gcc/expr.h:281
0xb88fed expand_return
        /home/marxin/Programming/gcc/gcc/cfgexpand.c:3639
0xb88fed expand_gimple_stmt_1
        /home/marxin/Programming/gcc/gcc/cfgexpand.c:3748
0xb88fed expand_gimple_stmt
        /home/marxin/Programming/gcc/gcc/cfgexpand.c:3875
0xb8e6d1 expand_gimple_basic_block
        /home/marxin/Programming/gcc/gcc/cfgexpand.c:5915
0xb903d7 execute
        /home/marxin/Programming/gcc/gcc/cfgexpand.c:6555
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