Subject: bug#39208: closed (Re: bug#39208: [3.0.0] Segfault while building on ARMv7)

From: [email-masked] (GNU bug Tracking System)
Date: Wed, 11 Mar 2020 20:22:03 +0000

Your bug report

#39208: [3.0.0] Segfault while building on ARMv7

which was filed against the guile package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to [email-masked].

-- 
39208: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=39208
GNU Bug Tracking System
Contact [email-masked] with problems

Subject: Re: bug#39208: [3.0.0] Segfault while building on ARMv7
From: Ludovic Courtès <[email-masked]>
Cc: [email-masked]
Date: Wed, 11 Mar 2020 21:21:03 +0100
List-Id: <debbugs-submit.debbugs.gnu.org>

Hi,

Ludovic Courtès <[email-masked]> skribis:

> Building 3.0.0 with Guix on ARMv7 reproducibly fails:
>
>   BOOTSTRAP GUILEC language/cps/loop-instrumentation.go
> wrote `language/cps/loop-instrumentation.go'
>   BOOTSTRAP GUILEC language/cps/peel-loops.go
> wrote `language/cps/effects-analysis.go'
>   BOOTSTRAP GUILEC language/cps/prune-top-level-scopes.go
> wrote `language/cps/licm.go'
>   BOOTSTRAP GUILEC language/cps/reify-primitives.go
> wrote `language/cps/prune-top-level-scopes.go'
>   BOOTSTRAP GUILEC language/cps/renumber.go
> wrote `language/cps/peel-loops.go'
>   BOOTSTRAP GUILEC language/cps/rotate-loops.go
> wrote `language/cps/reify-primitives.go'
>   BOOTSTRAP GUILEC language/cps/optimize.go
> wrote `language/cps/renumber.go'
>   BOOTSTRAP GUILEC language/cps/simplify.go
> wrote `language/cps/rotate-loops.go'
>   BOOTSTRAP GUILEC language/cps/self-references.go
> wrote `language/cps/optimize.go'
>   BOOTSTRAP GUILEC language/cps/slot-allocation.go
> wrote `language/cps/self-references.go'
>   BOOTSTRAP GUILEC language/cps/spec.go
> wrote `language/cps/simplify.go'
>   BOOTSTRAP GUILEC language/cps/specialize-primcalls.go
> wrote `language/cps/spec.go'
>   BOOTSTRAP GUILEC language/cps/specialize-numbers.go
> /gnu/store/nvkn00kq4x4g5wjjjvjj6rhzs0ihihxl-bash-minimal-5.0.7/bin/bash: line 6: 23019 Segmentation fault      (core dumped) GUILE_AUTO_COMPILE=0 ../meta/build-env guild compile --target="arm-unknown-linux-gnueabihf" -O1 -Oresolve-primitives -L "/tmp/guix-build-guile-next-3.0.0.drv-0/guile-3.0.0/module" -L "/tmp/guix-build-guile-next-3.0.0.drv-0/guile-3.0.0/guile-readline" -o "language/cps/specialize-primcalls.go" "../module/language/cps/specialize-primcalls.scm"
> make[2]: *** [Makefile:1931: language/cps/specialize-primcalls.go] Error 139
> make[2]: *** Waiting for unfinished jobs....
> wrote `language/cps/slot-allocation.go'
> wrote `language/cps/specialize-numbers.go'
> make[2]: Leaving directory '/tmp/guix-build-guile-next-3.0.0.drv-0/guile-3.0.0/bootstrap'
> make[1]: *** [Makefile:1849: all-recursive] Error 1

This also is fixed by commit 7c17655cd3d859bf0c5a86d9782a7788205fc05a
(<https://issues.guix.gnu.org/issue/39266>).

\o/

Ludo’.

Subject: [3.0.0] Segfault while building on ARMv7
From: Ludovic Courtès <[email-masked]>
To: [email-masked]
Date: Mon, 20 Jan 2020 17:33:48 +0100
List-Id: <debbugs-submit.debbugs.gnu.org>

Hello,

Building 3.0.0 with Guix on ARMv7 reproducibly fails:

--8<---------------cut here---------------start------------->8---
  BOOTSTRAP GUILEC language/cps/loop-instrumentation.go
wrote `language/cps/loop-instrumentation.go'
  BOOTSTRAP GUILEC language/cps/peel-loops.go
wrote `language/cps/effects-analysis.go'
  BOOTSTRAP GUILEC language/cps/prune-top-level-scopes.go
wrote `language/cps/licm.go'
  BOOTSTRAP GUILEC language/cps/reify-primitives.go
wrote `language/cps/prune-top-level-scopes.go'
  BOOTSTRAP GUILEC language/cps/renumber.go
wrote `language/cps/peel-loops.go'
  BOOTSTRAP GUILEC language/cps/rotate-loops.go
wrote `language/cps/reify-primitives.go'
  BOOTSTRAP GUILEC language/cps/optimize.go
wrote `language/cps/renumber.go'
  BOOTSTRAP GUILEC language/cps/simplify.go
wrote `language/cps/rotate-loops.go'
  BOOTSTRAP GUILEC language/cps/self-references.go
wrote `language/cps/optimize.go'
  BOOTSTRAP GUILEC language/cps/slot-allocation.go
wrote `language/cps/self-references.go'
  BOOTSTRAP GUILEC language/cps/spec.go
wrote `language/cps/simplify.go'
  BOOTSTRAP GUILEC language/cps/specialize-primcalls.go
wrote `language/cps/spec.go'
  BOOTSTRAP GUILEC language/cps/specialize-numbers.go
/gnu/store/nvkn00kq4x4g5wjjjvjj6rhzs0ihihxl-bash-minimal-5.0.7/bin/bash: line 6: 23019 Segmentation fault      (core dumped) GUILE_AUTO_COMPILE=0 ../meta/build-env guild compile --target="arm-unknown-linux-gnueabihf" -O1 -Oresolve-primitives -L "/tmp/guix-build-guile-next-3.0.0.drv-0/guile-3.0.0/module" -L "/tmp/guix-build-guile-next-3.0.0.drv-0/guile-3.0.0/guile-readline" -o "language/cps/specialize-primcalls.go" "../module/language/cps/specialize-primcalls.scm"
make[2]: *** [Makefile:1931: language/cps/specialize-primcalls.go] Error 139
make[2]: *** Waiting for unfinished jobs....
wrote `language/cps/slot-allocation.go'
wrote `language/cps/specialize-numbers.go'
make[2]: Leaving directory '/tmp/guix-build-guile-next-3.0.0.drv-0/guile-3.0.0/bootstrap'
make[1]: *** [Makefile:1849: all-recursive] Error 1
--8<---------------cut here---------------end--------------->8---

It seems to always happen while building ‘specialize-primcalls.go’.

(See
<https://ci.guix.gnu.org/log/8b8c0hxvm9qa5kff168vdr3943cc2s61-guile-next-3.0.0>.)

The backtrace is unfortunately not all that readable:

--8<---------------cut here---------------start------------->8---
Program terminated with signal SIGSEGV, Segmentation fault.
#0  0xf5c67b74 in ?? ()
[Current thread is 1 (Thread 0xf7fe8010 (LWP 23019))]
(gdb) bt
#0  0xf5c67b74 in ?? ()
#1  0xf7f3ffcc in scm_jit_enter_mcode (thread=0xdedc20,
    mcode=0xf5c67a00 " 8\r\032(-@\360c\203%i\250B\300\362_\203\240`\245m") at jit.c:5725
#2  0xf7093a40 in ?? ()
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
(gdb) info threads
  Id   Target Id                     Frame
* 1    Thread 0xf7fe8010 (LWP 23019) 0xf5c67b74 in ?? ()
  2    Thread 0xf7894460 (LWP 23042) 0xf7e8f034 in __libc_do_syscall ()
   from /gnu/store/n7c20pjm6q1xq1gqjqzzys1yk9fy7n1k-glibc-2.29/lib/libpthread.so.0
  3    Thread 0xf69a5460 (LWP 23045) 0xf7e8f034 in __libc_do_syscall ()
   from /gnu/store/n7c20pjm6q1xq1gqjqzzys1yk9fy7n1k-glibc-2.29/lib/libpthread.so.0
(gdb) frame 0
#0  0xf5c67b74 in ?? ()
(gdb) disassemble 0xf5c67a00,+500
Dump of assembler code from 0xf5c67a00 to 0xf5c67bf4:
   0xf5c67a00:  subs    r0, #32
   0xf5c67a02:  subs    r5, r1, r0
   0xf5c67a04:  cmp     r5, #40 ; 0x28
   0xf5c67a06:  bne.w   0xf5c680d0
   0xf5c67a0a:  ldr     r5, [r4, #16]
   0xf5c67a0c:  cmp     r0, r5
   0xf5c67a0e:  blt.w   0xf5c680d0
   0xf5c67a12:  str     r0, [r4, #8]
   0xf5c67a14:  ldr     r5, [r4, #88]   ; 0x58
   0xf5c67a16:  cmp     r5, #0
   0xf5c67a18:  beq.w   0xf5c68102
   0xf5c67a1c:  ldrt    r6, [r5]
   0xf5c67a20:  str     r6, [r4, #88]   ; 0x58
   0xf5c67a22:  str     r5, [r0, #24]
   0xf5c67a24:  movw    r5, #1293       ; 0x50d
   0xf5c67a28:  movs    r6, #0
   0xf5c67a2a:  str     r5, [r0, #16]
   0xf5c67a2c:  str     r6, [r0, #20]
   0xf5c67a2e:  ldr     r5, [r0, #24]
   0xf5c67a30:  ldr     r6, [r0, #16]
   0xf5c67a32:  str     r6, [r5, #0]
   0xf5c67a34:  ldr     r5, [r0, #32]
   0xf5c67a36:  ldr     r5, [r5, #4]
   0xf5c67a38:  str     r5, [r0, #16]
[…]
   0xf5c67b5e:  cmp     r5, #0
   0xf5c67b60:  ble.w   0xf5c67fce
   0xf5c67b64:  ldr     r5, [r0, #32]
   0xf5c67b66:  ldr     r5, [r5, #20]
   0xf5c67b68:  str     r5, [r0, #16]
   0xf5c67b6a:  ldr     r5, [r0, #16]
   0xf5c67b6c:  ldr     r5, [r5, #4]
   0xf5c67b6e:  str     r5, [r0, #16]
   0xf5c67b70:  mov.w   r12, #0
=> 0xf5c67b74:  ldrt    r5, [r12]
   0xf5c67b78:  str     r5, [r0, #8]
   0xf5c67b7a:  ldr     r5, [r0, #8]
   0xf5c67b7c:  ldr     r6, [r0, #16]
   0xf5c67b7e:  cmp     r5, r6
   0xf5c67b80:  bne.w   0xf5c67f80
[…]
(gdb) info registers
r0             0xf7093a20          4144577056
r1             0xf7093a48          4144577096
r2             0x0                 0
r3             0xf7a24001          4154605569
r4             0x74e00             478720
r5             0xdedc20            14605344
r6             0x0                 0
r7             0xf5c67a00          4123425280
r8             0x0                 0
r9             0x0                 0
r10            0xf7fc4bdc          4160506844
r11            0xf7fb5000          4160442368
r12            0x0                 0
sp             0xfffedc50          0xfffedc50
lr             0xf7f3ffcd          -135004211
pc             0xf5c67b74          0xf5c67b74
cpsr           0x200f0030          537854000
fpscr          0x60000000          1610612736
(gdb) frame 1
#1  0xf7f3ffcc in scm_jit_enter_mcode (thread=0xdedc20, 
    mcode=0xf5c67a00 " 8\r\032(-@\360c\203%i\250B\300\362_\203\240`\245m") at jit.c:5725
5725      enter_mcode (thread, mcode);
(gdb) info locals
No locals.
(gdb) p *thread
$2 = {next_thread = 0x5, vm = {ip = 0xdecd50, sp = 0x324602ae, fp = 0xdebc50, stack_limit = 0x30d, 
    compare_result = 72 'H', apply_hook_enabled = 130 '\202', return_hook_enabled = 82 'R', 
    next_hook_enabled = 1 '\001', abort_hook_enabled = 192 '\300', disable_mcode = 159 '\237', engine = 166 '\246', 
    unused = 1 '\001', stack_size = 15218, stack_bottom = 0x20d, apply_hook = 0x1528240, return_hook = 0x1a69fc0, 
    next_hook = 0x0, abort_hook = 0x5, stack_top = 0xdecd68, overflow_handler_stack = 0x28f45b3e, 
    registers = 0xdebc58, mra_after_abort = 0x20045 "", trace_level = -140048256}, pending_asyncs = 0x116ab78, 
  block_asyncs = 22184512, freelists = {0x20045, 0xf7a707ec, 0x1162bf8, 0x1528248, 0x5, 0x248360, 0x30999e00, 
    0xdebc60, 0x20d, 0x1528250, 0x1a69fc0, 0x0, 0x20045, 0xf7a70880, 0x1167440, 0x1528250, 0x5, 0xdecd80, 0x181aface, 
    0xdebc68, 0x20d, 0x1528258, 0x1a69fc0, 0x0, 0x20045, 0xf7a70880, 0x1167460, 0x1528258, 0x5, 0x248370, 0x91c2f1f, 
    0xdebc70}, pointerless_freelists = {0x30d, 0x7f1720, 0x1a69fc0, 0x1496, 0x30d, 0xdedd50, 0x96, 0x16, 0x5, 
    0x789740, 0x3275b29e, 0xdebc78, 0x30d, 0xdedd50, 0x16, 0x3fffffe, 0x30d, 0xdedd50, 0x96, 0x3fe, 0x5, 0xdecd98, 
    0x3afba8fc, 0xdebc80, 0x30d, 0x7f1720, 0x96, 0x16, 0x20d, 0x1528260, 0x1a69fc0, 0x0}, handle = 0x5, 
  pthread = 14601648, result = 0x38a97220, exited = 14597256, guile_mode = 131141, needs_unregister = -140048256, 
  wake = 0x1162128, sleep_cond = {__data = {{__wseq = 95281925316411917, __wseq32 = {__low = 525, 
          __high = 22184552}}, {__g1_start = 27697088, __g1_start32 = {__low = 27697088, __high = 0}}, __g_refs = {5, 
        7903072}, __g_size = {67881032, 14597264}, __g1_orig_size = 131141, __wrefs = 4154919040, __g_signals = {
        18228776, 22184552}}, 
    __size = "\r\002\000\000h\202R\001\300\237\246\001\000\000\000\000\005\000\000\000`\227x\000H\310\v\004\220\274\336\000E\000\002\000\200\b\247\367(&\026\001h\202R\001", __align = 95281925316411917}, sleep_pipe = {525, 22184560}, 
  dynamic_state = 0xa, dynstack = {base = 0x0, top = 0x5, limit = 0x789780}, continuation_root = 0x2db7da0c, 
  continuation_base = 0xdebc98, base = 0x20d, jit_state = 0xdede20}
--8<---------------cut here---------------end--------------->8---

Unfortunately I’m unable to reproduce the bug outside Guix’s build
environment, even with ASLR disabled (what guix-daemon does).

I wonder if that could be the same issue as
<https://issues.guix.gnu.org/issue/39118>.

I’ll happily take suggestions as to what debug info would be useful and
what I could bisect!

Ludo’.