[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

Andrew Pinski  changed:

   What|Removed |Added

 Status|WAITING |RESOLVED
 Resolution|--- |INVALID
   Keywords||GC, ice-on-valid-code

--- Comment #19 from Andrew Pinski  ---
No testcase provided in over 2 years so closing as invalid.

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[iains at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #18 from Iain Sandoe  ---
I'm testing regularly on macOS 10.14 (darwin18) - which I assume is the version
you meant?

Also on 8.3 and 9.2 .. (the results are posted to @testresults).

There was a PCH fixed (but that only manifested with -save-temps, so I don't
expect it to be directly relevant).

Right now, I can find no indication (or repeat) of this report - are you still
seeing it anywhere?

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[sje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #17 from Steve Ellcey  ---
The bug I was seeing on aarch64 turns out to be PR 91404.  It has now been
fixed.  I don't know if that patch will also fix the original bug seen on
Darwin or not.

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[sje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #16 from Steve Ellcey  ---
I built ggc-page.c with GCC_DEBUG_LEVEL 5 and I see:

Allocating object, requested size=360, actual=360 at 0x8726c210 on
0x10549200
Freeing object, actual size=360, at 0x8726c210 on 0x10549200

But then I wind up calling gt_ggc_mx_symtab_node with x_p of 0x8726c210.
I don't think I should be calling this (via ggc_mark_roots and  ggc_collect) if
it has already been freed.

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

Marek Polacek  changed:

   What|Removed |Added

 CC||mpolacek at gcc dot gnu.org

--- Comment #15 from Marek Polacek  ---
Those 0xa5 come from poison_pages in ggc-page.c, this call in particular:
 memset (object, 0xa5, size);

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[sje at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

Steve Ellcey  changed:

   What|Removed |Added

 CC||sje at gcc dot gnu.org

--- Comment #14 from Steve Ellcey  ---
I think I may be seeing this same bug on aarch64 when building the RAJA library
based on where I am dying in ggc_set_mark.  I have not been able to create a
preprocessed test case because when I compile the preprocessed sources the bug
does not happen.  Here is my segfault dump:

min.cpp:191:1: internal compiler error: Segmentation fault
  191 | } 
  | ^ 
0xf03b5f crash_signal
../../gcc/gcc/toplev.c:326
0x9cc86c lookup_page_table_entry
../../gcc/gcc/ggc-page.c:632
0x9cc86c ggc_set_mark(void const*)
../../gcc/gcc/ggc-page.c:1531
0xc6fe47 gt_ggc_mx_symtab_node(void*)
/home/sellcey/gcc-raja/obj-gcc/gcc/gtype-desc.c:1302
0xe17503 gt_ggc_ma_order
./gt-passes.h:31
0xbe44f3 ggc_mark_root_tab
../../gcc/gcc/ggc-common.c:77
0xbe4813 ggc_mark_roots()
../../gcc/gcc/ggc-common.c:94
0x9cd1fb ggc_collect()
../../gcc/gcc/ggc-page.c:2201
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See  for instructions.

When I look at gt_ggc_mx_symtab_node, the initial x_p pointer
that comes in is reasonable (0xa020c210) but after

xlimit = ((*xlimit).next);

The value of xlimit becomes 0xa5a5a5a5a5a5a5a5.  That looks
like a bogus value something might have put into memory
to poison it but I didn't see that specific string in
the GCC source tree anywhere.

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #13 from Richard Biener  ---
It might help (a little bit...) if you can run cc1plus in a debugger and at
the point of the crash print the value of p and provide a backtrace.

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[vincent.lextrait at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #12 from Vincent  ---
Thanks, Andrew.

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #11 from Andrew Pinski  ---
(In reply to Vincent from comment #10)
> Yes, sorry about that.
> Alas, I don't use them...

https://gcc.gnu.org/wiki/A_guide_to_testcase_reduction might be a good thing to
look into.

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[vincent.lextrait at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #10 from Vincent  ---
Yes, sorry about that.
Alas, I don't use them...

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #9 from Andrew Pinski  ---
(In reply to Andrew Pinski from comment #8)
> You still have not answered my question about precompiled headers?  Do you
> use them?

If so the workaround is not to use them at all.  See PR 61250 for information
on random PCH bugs on darwin (it only happens on darwin).

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #8 from Andrew Pinski  ---
You still have not answered my question about precompiled headers?  Do you use
them?

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[vincent.lextrait at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #7 from Vincent  ---
I understand.
It might have something to do with 67650, which was been in gcc since 2005, and
is fully reproducible until now (8.2.0). It seems to be a memory error too.
Sadly, nobody ever gave it a try.

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #6 from Andrew Pinski  ---
Read https://gcc.gnu.org/bugs/ .

There is nothing we can help you with without any way of trying to reproduce
the bug.

A crash in ggc_set_mark means one of two things:
* Precompiled Headers were used and there are some known issues on some hosts
(like Darwin/Mac OS)
* There is a bug in the compiler where we don't mark something for GC
correctly.

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[vincent.lextrait at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #5 from Vincent  ---
Hmm, hard to do, it is monumental and contains a ton of stuff I cannot share...
Sorry about that, I realize it makes diagnosis quite difficult.

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #4 from Andrew Pinski  ---
Can you add -save-temps and attach the preprocessed source?

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[vincent.lextrait at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #3 from Vincent  ---
It on MacOS Mojave 10.14.2.
The command line options are:
/usr/local/bin/g++-8 -c -DNDEBUG -O3 -fvisibility=hidden -Wall -Wextra
-pedantic-errors -DDARWIN -std=c++17 -fvisibility-inlines-hidden

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

--- Comment #2 from Andrew Pinski  ---
Oh what host is this on?

[Bug c++/89179] compiler error: in ggc_set_mark, at ggc-page.c:1532

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89179

Andrew Pinski  changed:

   What|Removed |Added

 Status|UNCONFIRMED |WAITING
   Last reconfirmed||2019-02-03
 Ever confirmed|0   |1

--- Comment #1 from Andrew Pinski  ---
Can you show the command line which is this happening?  Are you using
Precompiled Headers?