mirror of
https://github.com/espressif/binutils-gdb.git
synced 2025-08-02 02:35:00 +08:00
8a91fbdf3b
New in v2:
- Disable sharing only for -readnow objfiles, not all objfiles.
As described in PR 27541, we hit an internal error when loading a binary
the standard way and then loading it with the -readnow option:
$ ./gdb -nx -q --data-directory=data-directory ~/a.out -ex "set confirm off" -ex "file -readnow ~/a.out"
Reading symbols from /home/simark/a.out...
Reading symbols from ~/a.out...
/home/simark/src/binutils-gdb/gdb/dwarf2/read.c:8098: internal-error: void create_all_comp_units(dwarf2_per_objfile*): Assertion `per_objfile->per_bfd->all_comp_units.empty ()' failed.
This is a recurring problem that exposes a design issue in the DWARF
per-BFD sharing feature. Things work well when loading a binary with
the same method (with/without index, with/without readnow) twice in a
row. But they don't work so well when loading a binary with different
methods. See this previous fix, for example:
efb763a5ea35 ("gdb: check for partial symtab presence in dwarf2_initialize_objfile")
That one handled the case where the first load is normal (uses partial
symbols) and the second load uses an index.
The problem is that when loading an objfile with a method A, we create a
dwarf2_per_bfd and some dwarf2_per_cu_data and initialize them with the
data belonging to that method. When loading another obfile sharing the
same BFD but with a different method B, it's not clear how to re-use the
dwarf2_per_bfd/dwarf2_per_cu_data previously created, because they
contain the data specific to method A.
I think the most sensible fix would be to not share a dwarf2_per_bfd
between two objfiles loaded with different methods. That means that two
objfiles sharing the same BFD and loaded the same way would share a
dwarf2_per_bfd. Two objfiles sharing the same BFD but loaded with
different methods would use two different dwarf2_per_bfd structures.
However, this isn't a trivial change. So to fix the known issue quickly
(including in the gdb 10 branch), this patch just disables all
dwarf2_per_bfd sharing for objfiles using READNOW.
Generalize the gdb.base/index-cache-load-twice.exp test to test all
the possible combinations of loading a file with partial symtabs, index
and readnow. Move it to gdb.dwarf2, since it really exercises features
of the DWARF reader.
gdb/ChangeLog:
PR gdb/27541
* dwarf2/read.c (dwarf2_has_info): Don't share dwarf2_per_bfd
with objfiles using READNOW.
gdb/testsuite/ChangeLog:
PR gdb/27541
* gdb.base/index-cache-load-twice.exp: Remove.
* gdb.base/index-cache-load-twice.c: Remove.
* gdb.dwarf2/per-bfd-sharing.exp: New.
* gdb.dwarf2/per-bfd-sharing.c: New.
Change-Id: I9ffcf1e136f3e75242f70e4e58e4ba1fd3083389
29 lines
846 B
C
29 lines
846 B
C
/* This testcase is part of GDB, the GNU debugger.
|
|
|
|
Copyright 2020-2021 Free Software Foundation, Inc.
|
|
|
|
This program is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 3 of the License, or
|
|
(at your option) any later version.
|
|
|
|
This program is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with this program. If not, see <http://www.gnu.org/licenses/>. */
|
|
|
|
static
|
|
int foo (int a, int b)
|
|
{
|
|
return a + b;
|
|
}
|
|
|
|
int
|
|
main (void)
|
|
{
|
|
return foo (2, 3);
|
|
}
|