[Bug target/81639] New: ICE in rtl_verify_bb_insns, at cfgrtl.c:2669 with a naked function

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81639

            Bug ID: 81639
           Summary: ICE in rtl_verify_bb_insns, at cfgrtl.c:2669 with a
                    naked function
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marxin at gcc dot gnu.org
                CC: uros at gcc dot gnu.org
  Target Milestone: ---

Following test-case ICEs starting from r250736:

$ cat /tmp/ice.i
__attribute__ ((naked)) a () { b (); }

$ ./xgcc -B. /tmp/ice.i -Os
/tmp/ice.i:1:25: warning: return type defaults to ‘int’ [-Wimplicit-int]
 __attribute__ ((naked)) a () { b (); }
                         ^
/tmp/ice.i: In function ‘a’:
/tmp/ice.i:1:32: warning: implicit declaration of function ‘b’
[-Wimplicit-function-declaration]
 __attribute__ ((naked)) a () { b (); }
                                ^
/tmp/ice.i:1:1: error: in basic block 2:
 __attribute__ ((naked)) a () { b (); }
 ^~~~~~~~~~~~~
/tmp/ice.i:1:1: error: flow control insn inside a basic block
(insn 16 17 6 2 (trap_if (const_int 1 [0x1])
        (const_int 6 [0x6])) "/tmp/ice.i":1 -1
     (nil))
during RTL pass: pro_and_epilogue
/tmp/ice.i:1:1: internal compiler error: in rtl_verify_bb_insns, at
cfgrtl.c:2669
0x5a1de4 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
        ../../gcc/rtl-error.c:108
0x760305 rtl_verify_bb_insns
        ../../gcc/cfgrtl.c:2669
0x760305 rtl_verify_flow_info_1
        ../../gcc/cfgrtl.c:2755
0x760322 rtl_verify_flow_info
        ../../gcc/cfgrtl.c:2997
0x747bde verify_flow_info()
        ../../gcc/cfghooks.c:257
0xab31c9 execute_function_todo
        ../../gcc/passes.c:2002
0xab4222 execute_todo
        ../../gcc/passes.c:2044