[Bug debug/65521] New: [5 Regression] nondeterministic -fcompare-debug failures

[trippels at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65521

            Bug ID: 65521
           Summary: [5 Regression] nondeterministic -fcompare-debug
                    failures
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: debug
          Assignee: unassigned at gcc dot gnu.org
          Reporter: trippels at gcc dot gnu.org
              Host: powerpc64le-unknown-linux-gnu
            Target: powerpc64le-unknown-linux-gnu
             Build: powerpc64le-unknown-linux-gnu

on ppc64le I get nondeterministic -fcompare-debug failures during Linux
kernel build, e.g:

 % gcc -c -fcompare-debug -std=gnu89 -O2 ipmi_watchdog.i
gcc: error: ipmi_watchdog.i: -fcompare-debug failure
 % gcc -c -fcompare-debug -std=gnu89 -O2 ipmi_watchdog.i
 % gcc -c -fcompare-debug -std=gnu89 -O2 ipmi_watchdog.i
gcc: error: ipmi_watchdog.i: -fcompare-debug failure

 % diff -u ipmi_watchdog.gkd ipmi_watchdog.gk.gkd
--- ipmi_watchdog.gkd   2015-03-23 07:51:04.510095107 +0000
+++ ipmi_watchdog.gk.gkd        2015-03-23 07:51:05.100104842 +0000
@@ -90,7 +90,7 @@
 Declarations used by panic_smi_free, sorted by DECL_UID:
 0:   static void panic_recv_free (struct ipmi_recv_msg *);

-;; Function panic_smi_free (panic_smi_free, funcdef_no=1412, cgraph_uid=1422,
symbol_order=1513)
+;; Function panic_smi_free (panic_smi_free, funcdef_no=1408, cgraph_uid=1422,
symbol_order=1513)

 (note # 0 0 NOTE_INSN_DELETED)
 (note # 0 0 [bb 2] NOTE_INSN_BASIC_BLOCK)
@@ -531,7 +531,7 @@
 Declarations used by heartbeat_free_smi, sorted by DECL_UID:
 0:   static void heartbeat_free_recv (struct ipmi_recv_msg *);

-;; Function heartbeat_free_smi (heartbeat_free_smi, funcdef_no=1408,
cgraph_uid=1426, symbol_order=1526)
+;; Function heartbeat_free_smi (heartbeat_free_smi, funcdef_no=1412,
cgraph_uid=1426, symbol_order=1526)

 (note # 0 0 NOTE_INSN_DELETED)
 (note # 0 0 [bb 2] NOTE_INSN_BASIC_BLOCK)