[Bug tree-optimization/89280] New: [7/8/9 Regression] ICE: Segmentation fault (in is_gimple_reg_type)

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89280

            Bug ID: 89280
           Summary: [7/8/9 Regression] ICE: Segmentation fault (in
                    is_gimple_reg_type)
           Product: gcc
           Version: 9.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---

gcc-9.0.0-alpha20190210 snapshot (r268755) ICEs when compiling the following
testcase containing a call of function w/ returns_twice attribute:

int un;

void
r8 (void);

__attribute__ ((returns_twice)) int
vfork (void);

void
ef (int, int);

void
fx (void)
{
  for (;;)
    r8 ();

  ef (vfork (), un);
}

% gcc-9.0.0-alpha20190210 -c df3xie9n.c
during GIMPLE pass: cfg
df3xie9n.c: In function 'fx':
df3xie9n.c:13:1: internal compiler error: Segmentation fault
   13 | fx (void)
      | ^~
0xd6f9bf crash_signal
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20190210/work/gcc-9-20190210/gcc/toplev.c:326
0xda85b4 is_gimple_reg_type
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20190210/work/gcc-9-20190210/gcc/gimple-expr.h:75
0xda85b4 verify_gimple_call
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20190210/work/gcc-9-20190210/gcc/tree-cfg.c:3465
0xdbe2ca verify_gimple_in_cfg(function*, bool)
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20190210/work/gcc-9-20190210/gcc/tree-cfg.c:5370
0xc8a4df execute_function_todo
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20190210/work/gcc-9-20190210/gcc/passes.c:1977
0xc8b3fe execute_todo
       
/var/tmp/portage/sys-devel/gcc-9.0.0_alpha20190210/work/gcc-9-20190210/gcc/passes.c:2031