[Bug target/67002] New: [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[Bug target/67002] New: [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[glaubitz at physik dot fu-berlin.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

            Bug ID: 67002
           Summary: [5] [SH]: Bootstrap stage 2/3 comparison failure -
                    gcc/real.o differs
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: glaubitz at physik dot fu-berlin.de
                CC: doko at gcc dot gnu.org, kkojima at gcc dot gnu.org,
                    olegendo at gcc dot gnu.org
  Target Milestone: ---
            Target: sh*-*-*

Created attachment 36053
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36053&action=edit
gzip-compressed build log of gcc-5 (r225710) on sh4

Hello!

After checking with the gcc-5 build logs for the other architectures in Debian
which do not exhibit this particular comparison failure, I have decided to file
this as a bug against upstream. This particular comparison failure also doesn't
show with gcc-4.9, albeit I don't know whether gcc/real.o exist on gcc-4.9.

Here is the tail of the build log:

INFO=makeinfo --split-size=5000000 --split-size=5000000"  compare
make[4]: Entering directory '/«PKGBUILDDIR»/build'
make[5]: Entering directory '/«PKGBUILDDIR»/build'
rm -f stage_current
make[5]: Leaving directory '/«PKGBUILDDIR»/build'
Comparing stages 2 and 3
warning: gcc/cc1-checksum.o differs
warning: gcc/cc1plus-checksum.o differs
warning: gcc/cc1obj-checksum.o differs
warning: gcc/cc1objplus-checksum.o differs
Bootstrap comparison failure!
gcc/real.o differs
Makefile:20320: recipe for target 'compare' failed
make[4]: *** [compare] Error 1
make[4]: Leaving directory '/«PKGBUILDDIR»/build'
Makefile:20299: recipe for target 'stage3-bubble' failed
make[3]: *** [stage3-bubble] Error 2
make[3]: Leaving directory '/«PKGBUILDDIR»/build'
Makefile:20362: recipe for target 'bootstrap' failed
make[2]: *** [bootstrap] Error 2
make[2]: Leaving directory '/«PKGBUILDDIR»/build'
s=`cat status`; rm -f status; \
if [ $s -ne 0 ] && [ -z "$NO_CONFIG_LOG_DUMP" ]; then \
  for log in $(find /«PKGBUILDDIR»/build -name config.log); do \
    case "$log" in */prev-*) continue; esac; \
    echo LOGFILE START $log; \
    cat $log; \
    echo LOGFILE END $log; \
  done; \
fi; \
test $s -eq 0
LOGFILE START /«PKGBUILDDIR»/build/config.log
This file contains any messages produced by compilers while
running configure, to aid debugging if configure makes a mistake.

Attaching the full build log (gzip-compressed).

Adrian
>From gcc-bugs-return-493273-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Fri Jul 24 19:43:35 2015
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https://gcc.gnu.org/bugzilla/show_bug.cgi?idg001

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |INVALID

--- Comment #1 from H.J. Lu <hjl.tools at gmail dot com> ---
Pilot error.

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[olegendo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #1 from Oleg Endo <olegendo at gcc dot gnu.org> ---
That came out of a GCC version with has a known wrong-code bug (PR 66930)
Please try again with the patch
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66930#c10

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[glaubitz at physik dot fu-berlin.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #2 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-berlin.de> ---
I'm testing gcc-5_5.2.1-12 (r226105) now as suggested by Matthias.
Unfortunately, my SH7785LCR board crashed earlier today, so I had to restart
the build.

Once the build is finished, I will attached the stage2/3 versions of gcc/real.o
to this bug report.

The snapshot I am currently building does not the suggested patch from (PR
66930), so that we are sure to still run into the stage2/3 comparison failure
for further analysis. After that, I will do another build attempt with the
patch applied.

Adrian

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[glaubitz at physik dot fu-berlin.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #3 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-berlin.de> ---
Created attachment 36085
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36085&action=edit
gcc/real.o from different compiler stages

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[glaubitz at physik dot fu-berlin.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #4 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-berlin.de> ---
Here are the files, copied as follows:

root@tirpitz:/home/glaubitz> cd gcc-5-test_5.2.1-12/
root@tirpitz:..glaubitz/gcc-5-test_5.2.1-12> find . -name "real.o"
./gcc-5-5.2.1/build/gcc/real.o
./gcc-5-5.2.1/build/stage1-gcc/real.o
./gcc-5-5.2.1/build/prev-gcc/real.o
root@tirpitz:..glaubitz/gcc-5-test_5.2.1-12> mkdir ~/gcc-5-files
root@tirpitz:..glaubitz/gcc-5-test_5.2.1-12> cp -av
./gcc-5-5.2.1/build/gcc/real.o ~/gcc-5-files/real_stage3.o
‘./gcc-5-5.2.1/build/gcc/real.o’ -> ‘/root/gcc-5-files/real_stage3.o’
root@tirpitz:..glaubitz/gcc-5-test_5.2.1-12> cp -av
./gcc-5-5.2.1/build/stage1-gcc/real.o ~/gcc-5-files/real_stage1.o
‘./gcc-5-5.2.1/build/stage1-gcc/real.o’ -> ‘/root/gcc-5-files/real_stage1.o’
root@tirpitz:..glaubitz/gcc-5-test_5.2.1-12> cp -av
./gcc-5-5.2.1/build/prev-gcc/real.o ~/gcc-5-files/real_stage2.o
‘./gcc-5-5.2.1/build/prev-gcc/real.o’ -> ‘/root/gcc-5-files/real_stage2.o’
root@tirpitz:..glaubitz/gcc-5-test_5.2.1-12> cd
root@tirpitz:~> tar czf gcc-5-files.tgz gcc-5-files/
root@tirpitz:~>

Attaching this tarball.

Adrian
>From gcc-bugs-return-493612-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org Wed Jul 29 07:17:22 2015
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Subject: [Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs
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https://gcc.gnu.org/bugzilla/show_bug.cgi?idg002

--- Comment #5 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-berlin.de> ---
Some observations:

glaubitz@z6:~/gcc-5-files> sh4-linux-gnu-strip real_stage2.o
glaubitz@z6:~/gcc-5-files> ls -l
total 800
-rw-r--r-- 1 glaubitz glaubitz 376020 Jul 26 20:09 real_stage1.o
-rw-r--r-- 1 glaubitz glaubitz  33792 Jul 29 09:15 real_stage2.o
-rw-r--r-- 1 glaubitz glaubitz 401656 Jul 29 05:40 real_stage3.o
glaubitz@z6:~/gcc-5-files> sh4-linux-gnu-strip real_stage3.o
glaubitz@z6:~/gcc-5-files> ls -l
total 440
-rw-r--r-- 1 glaubitz glaubitz 376020 Jul 26 20:09 real_stage1.o
-rw-r--r-- 1 glaubitz glaubitz  33792 Jul 29 09:15 real_stage2.o
-rw-r--r-- 1 glaubitz glaubitz  33792 Jul 29 09:15 real_stage3.o
glaubitz@z6:~/gcc-5-files> sh4-linux-gnu-strip real_stage1.o
glaubitz@z6:~/gcc-5-files> ls -l
total 152
-rw-r--r-- 1 glaubitz glaubitz 80768 Jul 29 09:16 real_stage1.o
-rw-r--r-- 1 glaubitz glaubitz 33792 Jul 29 09:15 real_stage2.o
-rw-r--r-- 1 glaubitz glaubitz 33792 Jul 29 09:15 real_stage3.o
glaubitz@z6:~/gcc-5-files> diff real_stage2.o real_stage3.o
Binary files real_stage2.o and real_stage3.o differ
glaubitz@z6:~/gcc-5-files>

This was done on my main desktop, using a cross-toolchain.

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[glaubitz at physik dot fu-berlin.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #6 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-berlin.de> ---
And here is the diff from the disassembly:

glaubitz@z6:~/gcc-5-files> diff -u real*asm
--- real2.asm   2015-07-29 09:17:42.806123211 +0200
+++ real3.asm   2015-07-29 09:17:47.310013352 +0200
@@ -1,5 +1,5 @@

-real_stage2.o:     file format elf32-sh-linux
+real_stage3.o:     file format elf32-sh-linux


 Disassembly of section .text:
@@ -9328,7 +9328,7 @@
     4976:      03 a2           bra     0x4d80
     4978:      09 00           nop     
     497a:      5c d0           mov.l   0x4aec,r0       ! 4da8
-    497c:      5c db           mov.l   0x4af0,r11      ! 56e4
+    497c:      5c dc           mov.l   0x4af0,r12      ! 56e4
     497e:      0b 40           jsr     @r0
     4980:      01 e4           mov     #1,r4
     4982:      02 62           mov.l   @r0,r2
@@ -9347,18 +9347,18 @@
     499c:      f3 60           mov     r15,r0
     499e:      40 70           add     #64,r0
     49a0:      20 10           mov.l   r2,@(0,r0)
-    49a2:      0b 4b           jsr     @r11
+    49a2:      0b 4c           jsr     @r12
     49a4:      31 10           mov.l   r3,@(4,r0)
     49a6:      a8 2a           tst     r10,r10
     49a8:      02 8d           bt.s    0x49b0
     49aa:      83 6a           mov     r8,r10
     49ac:      ae a0           bra     0x4b0c
     49ae:      2d e1           mov     #45,r1
-    49b0:      50 dc           mov.l   0x4af4,r12      ! d80
+    49b0:      50 db           mov.l   0x4af4,r11      ! d80
     49b2:      f3 65           mov     r15,r5
     49b4:      f3 64           mov     r15,r4
     49b6:      30 75           add     #48,r5
-    49b8:      0b 4c           jsr     @r12
+    49b8:      0b 4b           jsr     @r11
     49ba:      18 74           add     #24,r4
     49bc:      09 e1           mov     #9,r1
     49be:      16 30           cmp/hi  r1,r0
@@ -9376,12 +9376,12 @@
     49d6:      13 6e           mov     r1,r14
     49d8:      01 e5           mov     #1,r5
     49da:      f3 64           mov     r15,r4
-    49dc:      0b 4b           jsr     @r11
+    49dc:      0b 4c           jsr     @r12
     49de:      18 74           add     #24,r4
     49e0:      f3 65           mov     r15,r5
     49e2:      f3 64           mov     r15,r4
     49e4:      30 75           add     #48,r5
-    49e6:      0b 4c           jsr     @r12
+    49e6:      0b 4b           jsr     @r11
     49e8:      18 74           add     #24,r4
     49ea:      30 70           add     #48,r0
     49ec:      00 2e           mov.b   r0,@r14
glaubitz@z6:~/gcc-5-files>

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[kkojima at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #7 from Kazumoto Kojima <kkojima at gcc dot gnu.org> ---
(In reply to John Paul Adrian Glaubitz from comment #6)
> And here is the diff from the disassembly:

A rare indeterminacy of the register choice.  Both codes are valid.
It seems very hard to find where has this indeterminacy come from.
Please follow Oleg's suggestion #c1.

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[glaubitz at physik dot fu-berlin.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #8 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-berlin.de> ---
(In reply to Kazumoto Kojima from comment #7)
> A rare indeterminacy of the register choice.  Both codes are valid.

Ok, that's what I thought as well.

> It seems very hard to find where has this indeterminacy come from.
> Please follow Oleg's suggestion #c1.

Since the patch mentioned in #c1 has already been committed, I'll just have to
wait for Matthias to update the SVN revision of the gcc-5 branch in Debian.

Maybe we can add gcc/real.o to the ignore list for the time being?

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[olegendo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #9 from Oleg Endo <olegendo at gcc dot gnu.org> ---
(In reply to John Paul Adrian Glaubitz from comment #8)
> 
> Maybe we can add gcc/real.o to the ignore list for the time being?

Not sure if this is a good idea.

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[olegendo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #11 from Oleg Endo <olegendo at gcc dot gnu.org> ---
(In reply to John Paul Adrian Glaubitz from comment #10)
> 
> Looking at the build log, it's only gcc/real.o where the comparison fails,
> all the others (except for the checksum files) are find. I think chances are
> that, if this is actually a real bug, it might show itself more pronounced
> when we use gcc-5 to build other packages.
> 
> Just look at how many bugs we were able to find in gcc-4.9 while using it as
> the standard host compiler on Debian sh4.

Yeah, for this purpose it can be ignored of course.  However, I guess for that
you might also just disable bootstrapping (configure with --disable-bootstrap).

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[glaubitz at physik dot fu-berlin.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #13 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-berlin.de> ---
(In reply to John Paul Adrian Glaubitz from comment #12)
> I'm collecting all the dumped output now and will upload. I will follow up
> with a download link quickly.

Here we go: http://users.physik.fu-berlin.de/~glaubitz/gcc-pr67002.tgz (approx.
171 MiB)

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[kkojima at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #14 from Kazumoto Kojima <kkojima at gcc dot gnu.org> ---
Created attachment 36117
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36117&action=edit
reduced test case

> Michael Karcher, who previously helped smashing some bugs in gcc for the SH
> target, had a go at this and he discovered that the difference between stage2
> and stage3 is the -gtoggle switch.

I've confirmed it even with cross 5/6 compilers.  The above reduced
C++ test case fails with "-S -O2 -fcompare-debug" on my 5/6 cross
sh4-linux/sh-elf g++.  It means that the generated insns differ
with/without -g.  It looks to me a target independent issue, though
I could be wrong about it.  With a quick look, rtl_pre pass behaves
differently with -g.  I've found PRs for -fcompare-debug like 63315,
65874, 65980, 66688 and 67043.

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[gcc-bugzilla at mkarcher dot dialup.fu-berlin.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #16 from Michael Karcher <gcc-bugzilla at mkarcher dot dialup.fu-berlin.de> ---
The bug seems to be quite similar to the infamous "sloth that was dropped on
the head as a baby"-bug Linus discovered (https://lkml.org/lkml/2014/7/24/584 ,
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61904). -fcompare-debug passes if
-fno-var-tracking-assignments is passed as compiler option.

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[olegendo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #17 from Oleg Endo <olegendo at gcc dot gnu.org> ---
(In reply to Michael Karcher from comment #16)

PR 61904 has been marked as a dup of PR 61801, which has been marked as fixed. 
So this must be some other bug.

When compiling the same code as C and as C++ there might be differences because
it's two different language front ends.  Sometimes we get cases like PR 56365.

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[kkojima at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #18 from Kazumoto Kojima <kkojima at gcc dot gnu.org> ---
(In reply to Michael Karcher from comment #15)
The first different line of diff of the .pre dumps of Michael's
test case with/without -g is:

< Expression hash table (53 buckets, 12 entries)
---
> Expression hash table (51 buckets, 12 entries)

It means that gcse.c:alloc_hash_table allocates the table with
different number of buckets with -g.
It looks emit_rtl.c:get_max_insn_count returns different values
with/without -g at rtl_pre pass.  This shouldn't happen.
The comment of get_max_insn_count says:

  /* The table size must be stable across -g, to avoid codegen
     differences due to debug insns, and not be affected by
     -fmin-insn-uid, to avoid excessive table size and to simplify
     debugging of -fcompare-debug failures.  */

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[kkojima at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #19 from Kazumoto Kojima <kkojima at gcc dot gnu.org> ---
(In reply to Kazumoto Kojima from comment #18)
In the problematic situation, get_max_insn_count returns the false
value after

  if (MAY_HAVE_DEBUG_INSNS)
    expand_debug_locations ();

in pass_expand::execute (function *fun).  expand_debug_locations
calls sh_recog_treg_set_expr indirectly at this very early stage
to compute rtx costs.  sh_recog_treg_set_expr makes some set insns
and they cause the differences of cur_insn_uid with -g.  Oleg, how
about the patch below?  My first trial was --cur_insn_uid just
after make_insn_raw there but I'm afraid that it will make another
surprise.

diff --git a/config/sh/sh.c b/config/sh/sh.c
index f429193..450d634 100644
--- a/config/sh/sh.c
+++ b/config/sh/sh.c
@@ -14165,6 +14165,12 @@ sh_recog_treg_set_expr (rtx op, machine_mode mode)
   if (!can_create_pseudo_p ())
     return false;

+  /* expand_debug_locations may call this to compute rtx costs at
+     very early stage.  In that case, don't make new insns here to
+     avoid codegen differences with -g. */
+  if (currently_expanding_to_rtl)
+    return false;
+
   /* We are going to invoke recog in a re-entrant way and thus
      have to capture its current state and restore it afterwards.  */
   recog_data_d prev_recog_data = recog_data;

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[kkojima at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #21 from Kazumoto Kojima <kkojima at gcc dot gnu.org> ---
(In reply to Oleg Endo from comment #20)
> Yes, that looks OK.  treg_set_expr-something recog matching is actually only
> required during combine.  The simpler forms like (reg:SI T_REG) could also
> be required during expansion.

Thanks.  I'll commit it when the usual test is done.

> Hm ... actually it should work.  The temporary rtx insn is not used for
> anything else, so that assigned insn uid will never appear anywhere. 
> However, it's probably better to have one "static rtx_insn" to avoid
> constructing the temporary rtx over and over again.  Unfortunately the
> gen_rtx* functions allocate rtx objects always on the GC heap.

Yes, it works.  I'm uncomfortable with it because the current use of
crtl->emit.x_cur_insn_uid aka cur_insn_uid is limitted to emit-rtl.c.
I think that the use of that field outside of emit-rtl.c is unexpected.
Also it doesn't sound good to add a new interface to access that field
there.  After all, your "static rtx_insn" is the right thing to do.

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[olegendo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #22 from Oleg Endo <olegendo at gcc dot gnu.org> ---
(In reply to Kazumoto Kojima from comment #21)
> 
> Yes, it works.  I'm uncomfortable with it because the current use of
> crtl->emit.x_cur_insn_uid aka cur_insn_uid is limitted to emit-rtl.c.
> I think that the use of that field outside of emit-rtl.c is unexpected.
> Also it doesn't sound good to add a new interface to access that field
> there.  After all, your "static rtx_insn" is the right thing to do.

OK.  I will try to implement that "static rtx_insn" thing, after I have
finished the patch attachment 36012, which makes some changes to treg_set_expr.

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[kkojima at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #23 from Kazumoto Kojima <kkojima at gcc dot gnu.org> ---
Author: kkojima
Date: Fri Aug  7 20:41:25 2015
New Revision: 226726

URL: https://gcc.gnu.org/viewcvs?rev=226726&root=gcc&view=rev
Log:
PR target/67002
* config/sh/sh.c (sh_recog_treg_set_expr): Return false during
expand phase to avoid codegen differences with -g.


Modified:
    branches/gcc-5-branch/gcc/ChangeLog
    branches/gcc-5-branch/gcc/config/sh/sh.c

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[kkojima at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #24 from Kazumoto Kojima <kkojima at gcc dot gnu.org> ---
Author: kkojima
Date: Fri Aug  7 08:11:45 2015
New Revision: 226715

URL: https://gcc.gnu.org/viewcvs?rev=226715&root=gcc&view=rev
Log:
PR target/67002
* config/sh/sh.c (sh_recog_treg_set_expr): Return false during
expand phase to avoid codegen differences with -g.


Modified:
    branches/trunk/gcc/ChangeLog
    branches/trunk/gcc/config/sh/sh.c

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[glaubitz at physik dot fu-berlin.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #25 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-berlin.de> ---
Ok, this seems to have been fixed:

Comparing stages 2 and 3
warning: gcc/cc1objplus-checksum.o differs
warning: gcc/cc1-checksum.o differs
warning: gcc/cc1plus-checksum.o differs
warning: gcc/cc1obj-checksum.o differs
Comparison successful.

gcc-5 is still building though and we might run into another issue, but cross
your fingers :).

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[olegendo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #26 from Oleg Endo <olegendo at gcc dot gnu.org> ---
(In reply to John Paul Adrian Glaubitz from comment #25)
> Ok, this seems to have been fixed:
>

Although this PR could be marked as fixed, I'd like to keep it open.  It will
remind me of the "static rtx_insn" mentioned above.

Please open a new PR if there is another boostrapping issue.

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[glaubitz at physik dot fu-berlin.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #27 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-berlin.de> ---
(In reply to Oleg Endo from comment #26)
> Please open a new PR if there is another boostrapping issue.

I'm afraid that might actually be the case even though I'm not sure whether
it's a bug in gcc or elsewhere.

What happens is that g++ seems to get stuck in stage3 when compiling
src/gcc/c-family/c-common.c. After a while, the build daemon will just kill g++
because of inactivity. Interestingly, c-common.o seems to compile fine though.

Should I open a new PR?

Adrian

[Bug target/67002] [5] [SH]: Bootstrap stage 2/3 comparison failure - gcc/real.o differs

[glaubitz at physik dot fu-berlin.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67002

--- Comment #28 from John Paul Adrian Glaubitz <glaubitz at physik dot fu-berlin.de> ---
(In reply to John Paul Adrian Glaubitz from comment #27)
> What happens is that g++ seems to get stuck in stage3 when compiling
> src/gcc/c-family/c-common.c. After a while, the build daemon will just kill
> g++ because of inactivity. Interestingly, c-common.o seems to compile fine
> though.

Ok, it actually went further now. It was just stuck for over an hour. Looking
at strace showed that g++ was allocating memory (brk syscalls).

Will report back.