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* [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
@ 2022-09-14 8:28 vries at gcc dot gnu.org
2022-09-14 8:30 ` [Bug symtab/29572] " vries at gcc dot gnu.org
` (11 more replies)
0 siblings, 12 replies; 13+ messages in thread
From: vries at gcc dot gnu.org @ 2022-09-14 8:28 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
Bug ID: 29572
Summary: [gdb/symtab] read.h:298: internal-error: length:
Assertion `m_length != 0' failed.
Product: gdb
Version: HEAD
Status: NEW
Severity: normal
Priority: P2
Component: symtab
Assignee: unassigned at sourceware dot org
Reporter: vries at gcc dot gnu.org
Target Milestone: ---
When running with target board cc-with-debug-names, I run into:
...
FAIL: gdb.dwarf2/dw2-symtab-includes-lookup.exp: ptype myint (GDB internal
error)
FAIL: gdb.dwarf2/enqueued-cu-base-addr.exp: ptype foo (GDB internal error)
FAIL: gdb.dwarf2/enqueued-cu-base-addr.exp: CU addr found
FAIL: gdb.dwarf2/opaque-type-lookup.exp: p variable_a (GDB internal error)
FAIL: gdb.dwarf2/opaque-type-lookup.exp: p variable_b (GDB internal error)
FAIL: gdb.dwarf2/varval.exp: print bad_die_val1 (GDB internal error)
...
Command-line reproducer of first fail:
...
$ gdb -q -batch
./outputs/gdb.dwarf2/dw2-symtab-includes-lookup/dw2-symtab-includes-lookup -ex
"ptype myint"
/home/vries/gdb_versions/devel/src/gdb/dwarf2/read.h:298: internal-error:
length: Assertion `m_length != 0' failed.
...
We're trying to find (in dwarf2_find_containing_comp_unit) the containing CU
for DIE 0xa5:
...
Compilation Unit @ offset 0x9a:
Length: 0x16 (32-bit)
Version: 4
Abbrev Offset: 0x5a
Pointer Size: 8
<0><a5>: Abbrev Number: 2 (DW_TAG_partial_unit)
<a6> DW_AT_stmt_list : 0xe8
<1><aa>: Abbrev Number: 3 (DW_TAG_base_type)
<ab> DW_AT_byte_size : 4
<ac> DW_AT_encoding : 5 (signed)
<ad> DW_AT_name : myint
<1><b3>: Abbrev Number: 0
...
which is 0x9a, but when getting the length of the unit, it turns out to be 0.
This is a regression since commit 1c04f72368c ("[gdb/symtab] Fix assert in
set_length"), which starting keeping length at 0 when reading the CU list from
.debug_names, and relied on a later set_length to fill in the actual length.
This happens fine for CUs, but in this case it's a PU.
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* [Bug symtab/29572] [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
2022-09-14 8:28 [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed vries at gcc dot gnu.org
@ 2022-09-14 8:30 ` vries at gcc dot gnu.org
2022-09-14 8:31 ` vries at gcc dot gnu.org
` (10 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: vries at gcc dot gnu.org @ 2022-09-14 8:30 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
--- Comment #1 from Tom de Vries <vries at gcc dot gnu.org> ---
Backtrace at assert:
...
(gdb) bt
#0 __GI_raise (sig=6) at ../sysdeps/unix/sysv/linux/raise.c:51
#1 0x00007ffff4a05375 in __GI_abort () at abort.c:79
#2 0x0000000000c81e49 in dump_core ()
at /home/vries/gdb_versions/devel/src/gdb/utils.c:202
#3 0x0000000000c8247f in internal_vproblem(internal_problem *, const char *,
int, const char *, typedef __va_list_tag __va_list_tag *) (
problem=0x2785c60 <internal_error_problem>,
file=0x14cf880 "/home/vries/gdb_versions/devel/src/gdb/dwarf2/read.h",
line=298, fmt=0x14cf850 "%s: Assertion `%s' failed.", ap=0x7fffffff90e8)
at /home/vries/gdb_versions/devel/src/gdb/utils.c:450
#4 0x0000000000c82555 in internal_verror (
file=0x14cf880 "/home/vries/gdb_versions/devel/src/gdb/dwarf2/read.h",
line=298, fmt=0x14cf850 "%s: Assertion `%s' failed.", ap=0x7fffffff90e8)
at /home/vries/gdb_versions/devel/src/gdb/utils.c:476
#5 0x00000000013cef2f in internal_error (
file=0x14cf880 "/home/vries/gdb_versions/devel/src/gdb/dwarf2/read.h",
line=298, fmt=0x14cf850 "%s: Assertion `%s' failed.")
at /home/vries/gdb_versions/devel/src/gdbsupport/errors.cc:58
#6 0x00000000006b1b37 in dwarf2_per_cu_data::length (this=0x369e3a0)
at /home/vries/gdb_versions/devel/src/gdb/dwarf2/read.h:298
#7 0x00000000007121d2 in dwarf2_find_containing_comp_unit (
sect_off=(unknown: 0xa5), offset_in_dwz=0,
all_comp_units=std::vector of length 9, capacity 9 = {...})
at /home/vries/gdb_versions/devel/src/gdb/dwarf2/read.c:23558
#8 0x0000000000712280 in dwarf2_find_containing_comp_unit (
sect_off=(unknown: 0xa5), offset_in_dwz=0, per_bfd=0x369cf80)
at /home/vries/gdb_versions/devel/src/gdb/dwarf2/read.c:23576
#9 0x00000000006ec16b in process_imported_unit_die (die=0x36bdc50,
cu=0x2d26d00)
at /home/vries/gdb_versions/devel/src/gdb/dwarf2/read.c:8577
#10 0x00000000006ec6c8 in process_die (die=0x36bdc50, cu=0x2d26d00)
at /home/vries/gdb_versions/devel/src/gdb/dwarf2/read.c:8735
#11 0x00000000006ee4f4 in read_file_scope (die=0x36bdb50, cu=0x2d26d00)
at /home/vries/gdb_versions/devel/src/gdb/dwarf2/read.c:9642
#12 0x00000000006ec448 in process_die (die=0x36bdb50, cu=0x2d26d00)
at /home/vries/gdb_versions/devel/src/gdb/dwarf2/read.c:8643
#13 0x00000000006ebbcc in process_full_comp_unit (cu=0x2d26d00,
pretend_language=language_minimal)
at /home/vries/gdb_versions/devel/src/gdb/dwarf2/read.c:8412
#14 0x00000000006e91f6 in process_queue (per_objfile=0x2d28540)
at /home/vries/gdb_versions/devel/src/gdb/dwarf2/read.c:7658
#15 0x00000000006db090 in dw2_do_instantiate_symtab (per_cu=0x369e420,
per_objfile=0x2d28540, skip_partial=false)
at /home/vries/gdb_versions/devel/src/gdb/dwarf2/read.c:2063
#16 0x00000000006db139 in dw2_instantiate_symtab (per_cu=0x369e420,
per_objfile=0x2d28540, skip_partial=false)
at /home/vries/gdb_versions/devel/src/gdb/dwarf2/read.c:2085
...
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* [Bug symtab/29572] [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
2022-09-14 8:28 [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed vries at gcc dot gnu.org
2022-09-14 8:30 ` [Bug symtab/29572] " vries at gcc dot gnu.org
@ 2022-09-14 8:31 ` vries at gcc dot gnu.org
2022-09-14 9:52 ` vries at gcc dot gnu.org
` (9 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: vries at gcc dot gnu.org @ 2022-09-14 8:31 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
Tom de Vries <vries at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |tromey at sourceware dot org
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* [Bug symtab/29572] [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
2022-09-14 8:28 [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed vries at gcc dot gnu.org
2022-09-14 8:30 ` [Bug symtab/29572] " vries at gcc dot gnu.org
2022-09-14 8:31 ` vries at gcc dot gnu.org
@ 2022-09-14 9:52 ` vries at gcc dot gnu.org
2022-09-14 9:53 ` vries at gcc dot gnu.org
` (8 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: vries at gcc dot gnu.org @ 2022-09-14 9:52 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
--- Comment #2 from Tom de Vries <vries at gcc dot gnu.org> ---
Created attachment 14335
--> https://sourceware.org/bugzilla/attachment.cgi?id=14335&action=edit
Demonstrator patch
This is an alternative way of fixing PR29453.
Basically, we look into the CU header to find the length.
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* [Bug symtab/29572] [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
2022-09-14 8:28 [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed vries at gcc dot gnu.org
` (2 preceding siblings ...)
2022-09-14 9:52 ` vries at gcc dot gnu.org
@ 2022-09-14 9:53 ` vries at gcc dot gnu.org
2022-09-14 12:30 ` vries at gcc dot gnu.org
` (7 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: vries at gcc dot gnu.org @ 2022-09-14 9:53 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
--- Comment #3 from Tom de Vries <vries at gcc dot gnu.org> ---
(In reply to Tom de Vries from comment #2)
> Created attachment 14335 [details]
> Demonstrator patch
>
> This is an alternative way of fixing PR29453.
>
> Basically, we look into the CU header to find the length.
The more intrusive, but more maintainable version of this would be to just
always call create_all_comp_units, not just for readnow and cooked index, but
also for .debug_names and .gdb_index.
Tom, I think you suggested that already somewhere.
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* [Bug symtab/29572] [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
2022-09-14 8:28 [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed vries at gcc dot gnu.org
` (3 preceding siblings ...)
2022-09-14 9:53 ` vries at gcc dot gnu.org
@ 2022-09-14 12:30 ` vries at gcc dot gnu.org
2022-09-14 13:02 ` vries at gcc dot gnu.org
` (6 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: vries at gcc dot gnu.org @ 2022-09-14 12:30 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
--- Comment #4 from Tom de Vries <vries at gcc dot gnu.org> ---
(In reply to Tom de Vries from comment #3)
> (In reply to Tom de Vries from comment #2)
> > Created attachment 14335 [details]
> > Demonstrator patch
> >
> > This is an alternative way of fixing PR29453.
> >
> > Basically, we look into the CU header to find the length.
>
> The more intrusive, but more maintainable version of this would be to just
> always call create_all_comp_units, not just for readnow and cooked index,
> but also for .debug_names and .gdb_index.
>
> Tom, I think you suggested that already somewhere.
Hmm, this also provides us with an opportunity to fix PR25969.
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* [Bug symtab/29572] [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
2022-09-14 8:28 [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed vries at gcc dot gnu.org
` (4 preceding siblings ...)
2022-09-14 12:30 ` vries at gcc dot gnu.org
@ 2022-09-14 13:02 ` vries at gcc dot gnu.org
2022-09-14 13:50 ` vries at gcc dot gnu.org
` (5 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: vries at gcc dot gnu.org @ 2022-09-14 13:02 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
--- Comment #5 from Tom de Vries <vries at gcc dot gnu.org> ---
Created attachment 14336
--> https://sourceware.org/bugzilla/attachment.cgi?id=14336&action=edit
Tentative patch
Currently testing
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* [Bug symtab/29572] [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
2022-09-14 8:28 [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed vries at gcc dot gnu.org
` (5 preceding siblings ...)
2022-09-14 13:02 ` vries at gcc dot gnu.org
@ 2022-09-14 13:50 ` vries at gcc dot gnu.org
2022-09-14 15:49 ` vries at gcc dot gnu.org
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From: vries at gcc dot gnu.org @ 2022-09-14 13:50 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
--- Comment #6 from Tom de Vries <vries at gcc dot gnu.org> ---
(In reply to Tom de Vries from comment #5)
> Created attachment 14336 [details]
> Tentative patch
>
> Currently testing
Hmm, I guess I'll need to give create_signatured_type_table_from_debug_names
the same treatment as create_cus_from_debug_names, that is, transform it into
check_signatured_type_table_from_debug_names.
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* [Bug symtab/29572] [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
2022-09-14 8:28 [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed vries at gcc dot gnu.org
` (6 preceding siblings ...)
2022-09-14 13:50 ` vries at gcc dot gnu.org
@ 2022-09-14 15:49 ` vries at gcc dot gnu.org
2023-07-20 12:44 ` vries at gcc dot gnu.org
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11 siblings, 0 replies; 13+ messages in thread
From: vries at gcc dot gnu.org @ 2022-09-14 15:49 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
--- Comment #7 from Tom de Vries <vries at gcc dot gnu.org> ---
(In reply to Tom de Vries from comment #5)
> Created attachment 14336 [details]
> Tentative patch
>
> Currently testing
Testing went fine (native + target board cc-with-debug-names), so I suppose
it's just a question of adding the TU handling bit.
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* [Bug symtab/29572] [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
2022-09-14 8:28 [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed vries at gcc dot gnu.org
` (7 preceding siblings ...)
2022-09-14 15:49 ` vries at gcc dot gnu.org
@ 2023-07-20 12:44 ` vries at gcc dot gnu.org
2023-08-10 13:46 ` cvs-commit at gcc dot gnu.org
` (2 subsequent siblings)
11 siblings, 0 replies; 13+ messages in thread
From: vries at gcc dot gnu.org @ 2023-07-20 12:44 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
--- Comment #8 from Tom de Vries <vries at gcc dot gnu.org> ---
Fix was submitted here:
https://sourceware.org/pipermail/gdb-patches/2022-September/192031.html
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* [Bug symtab/29572] [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
2022-09-14 8:28 [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed vries at gcc dot gnu.org
` (8 preceding siblings ...)
2023-07-20 12:44 ` vries at gcc dot gnu.org
@ 2023-08-10 13:46 ` cvs-commit at gcc dot gnu.org
2023-12-06 9:29 ` cvs-commit at gcc dot gnu.org
2023-12-06 9:35 ` vries at gcc dot gnu.org
11 siblings, 0 replies; 13+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2023-08-10 13:46 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
--- Comment #9 from cvs-commit at gcc dot gnu.org <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Tom de Vries <vries@sourceware.org>:
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=107ab8d45df84b442ce2d79c6dda3a9b3afc80d5
commit 107ab8d45df84b442ce2d79c6dda3a9b3afc80d5
Author: Tom de Vries <tdevries@suse.de>
Date: Thu Aug 10 15:46:30 2023 +0200
[gdb/testsuite] Improve failure mode in
gdb.dwarf2/enqueued-cu-base-addr.exp
I ran test-case gdb.dwarf2/enqueued-cu-base-addr.exp with target board
cc-with-debug-names, and ran into:
...
FAIL: gdb.dwarf2/enqueued-cu-base-addr.exp: ptype foo (GDB internal error)
FAIL: gdb.dwarf2/enqueued-cu-base-addr.exp: CU addr found
...
The first FAIL is a known issue, PR symtab/29572.
The following FAIL is a consequence of the first FAIL, so require for the
second test that the first test passes.
Tested on x86_64-linux, with target boards unix and cc-with-debug-names.
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* [Bug symtab/29572] [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
2022-09-14 8:28 [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed vries at gcc dot gnu.org
` (9 preceding siblings ...)
2023-08-10 13:46 ` cvs-commit at gcc dot gnu.org
@ 2023-12-06 9:29 ` cvs-commit at gcc dot gnu.org
2023-12-06 9:35 ` vries at gcc dot gnu.org
11 siblings, 0 replies; 13+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2023-12-06 9:29 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
--- Comment #10 from Sourceware Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Tom de Vries <vries@sourceware.org>:
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=b17ef9dcd8d16eedf4e60565cd7701698b5a0b6b
commit b17ef9dcd8d16eedf4e60565cd7701698b5a0b6b
Author: Tom de Vries via Gdb-patches <gdb-patches@sourceware.org>
Date: Wed Dec 6 10:29:17 2023 +0100
[gdb/symtab] Redo "Fix assert in set_length"
This reverts commit 1c04f72368c ("[gdb/symtab] Fix assert in set_length"),
due
to a regression reported in PR29572, and implements a different fix for
PR29453.
The fix is to not use the CU table in a .debug_names section to construct
all_units, but instead use create_all_units, and then verify the CU
table from .debug_names. This also fixes PR25969, so remove the KFAIL.
Approved-By: Tom Tromey <tom@tromey.com>
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29572
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=25969
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* [Bug symtab/29572] [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed.
2022-09-14 8:28 [Bug symtab/29572] New: [gdb/symtab] read.h:298: internal-error: length: Assertion `m_length != 0' failed vries at gcc dot gnu.org
` (10 preceding siblings ...)
2023-12-06 9:29 ` cvs-commit at gcc dot gnu.org
@ 2023-12-06 9:35 ` vries at gcc dot gnu.org
11 siblings, 0 replies; 13+ messages in thread
From: vries at gcc dot gnu.org @ 2023-12-06 9:35 UTC (permalink / raw)
To: gdb-prs
https://sourceware.org/bugzilla/show_bug.cgi?id=29572
Tom de Vries <vries at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
Resolution|--- |FIXED
Target Milestone|--- |15.1
--- Comment #11 from Tom de Vries <vries at gcc dot gnu.org> ---
Fixed.
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