[Bug target/114432] [13 Regression] ICE in connect_traces, at dwarf2cfi.cc:3079 on s390x-linux-gnu

["stefansf at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=114432

--- Comment #4 from Stefan Schulze Frielinghaus <stefansf at gcc dot gnu.org> ---
Ignore the previous comment.  With -fstack-check and -mbackchain we have for
trace 2 an incoming edge from trace 1 (fallthrough) where
cur_trace->end_true_args_size == 48 and from further incoming edges as e.g.
from trace 7 where cur_trace->end_true_args_size == 0 which is why the
args_size is supposed to be undefined.

Interestingly, trace 2 resides in the function body whereas trace 7 resides in
the epilogue, i.e., we have a jump from the epilogue into the function body:

(note 597 810 634 NOTE_INSN_PROLOGUE_END)
...
(insn 635 677 566 (set (reg/f:DI 15 %r15)
        (plus:DI (reg/f:DI 15 %r15)
            (const_int 8216 [0x2018])))
"libalog-0.6.2/src/alog-active_logger.adb":244:4 1481 {*la_64}
     (expr_list:REG_ARGS_SIZE (const_int 48 [0x30])
        (nil)))
...
(code_label 48 573 49 152 (nil) [2 uses])
...
(note 673 768 599 NOTE_INSN_EPILOGUE_BEG)
...
(insn 159 163 160 (set (reg/f:DI 15 %r15)
        (reg/f:DI 6 %r6 [orig:79 saved_stack.186_50 ] [79]))
"libalog-0.6.2/src/alog-active_logger.adb":260:0 discrim 10 1477 {*movdi_64}
     (expr_list:REG_DEAD (reg/f:DI 6 %r6 [orig:79 saved_stack.186_50 ] [79])
        (expr_list:REG_ARGS_SIZE (const_int 0 [0])
            (nil))))
...
(jump_insn 645 644 646 (set (pc)
        (label_ref 48)) 2170 {*jump64}
     (nil)
 -> 48)

This is also the case when -fno-shrink-wrap is used.