forked from Imagelibrary/binutils-gdb
94de78f9d0
Commit bedd6a7a44 ("gdb/dwarf: track compilation and type unit count")
causes this internal error:
$ ./gdb -nx -q --data-directory=data-directory testsuite/outputs/gdb.dwarf2/debug-names-duplicate-cu/debug-names-duplicate-cu -ex "save gdb-index -dwarf-5 /tmp" -batch
warning: Section .debug_names has incorrect number of CUs in CU table, ignoring .debug_names.
/home/smarchi/src/binutils-gdb/gdb/dwarf2/index-write.c:1454: internal-error: write_debug_names: Assertion `comp_unit_counter == per_bfd->num_comp_units' failed.
This is visible when running this test:
$ make check TESTS="gdb.dwarf2/debug-names-duplicate-cu.exp" RUNTESTFLAGS="--target_board=cc-with-debug-names"
...
Running /home/smarchi/src/binutils-gdb/gdb/testsuite/gdb.dwarf2/debug-names-duplicate-cu.exp ...
gdb compile failed, warning: Section .debug_names has incorrect number of CUs in CU table, ignoring .debug_names.
/home/smarchi/src/binutils-gdb/gdb/dwarf2/index-write.c:1454: internal-error: write_debug_names: Assertion `comp_unit_counter == per_bfd->num_comp_units' failed.
...
=== gdb Summary ===
# of untested testcases 1
However, it's easy to miss because it only causes an "UNTESTED" to be
recorded, not a FAIL or UNRESOLVED. This is because the problem happens
while trying to create the .debug_names index, as part of the test case
compilation.
The problem is: when we bail out from using .debug_names because we
detect it is inconsistent with the units in .debug_info, we clear
per_bfd->all_units, to destroy all units previously created, before
proceeding to read the units with an index. However, we don't clear
per_bfd->num_{comp,type}_units. As a result, per_bfd->all_units
contains one unit, while per_bfd->num_comp_units is 2. Whenever we
clear per_bfd->all_units, we should also clear
per_bfd->num_{comp,type}_units.
While at it, move this logic inside a scoped object.
I added an assertion in finalize_all_units to verify that the size of
per_bfd->all_units equals per_bfd->num_comp_units +
per_bfd->num_type_units. This makes the problem (if omitting the fix)
visible when running gdb.dwarf2/debug-names-duplicate-cu.exp with the
unix (default) target board:
ERROR: Couldn't load debug-names-duplicate-cu into GDB (GDB internal error).
FAIL: gdb.dwarf2/debug-names-duplicate-cu.exp: find index type (GDB internal error)
FAIL: gdb.dwarf2/debug-names-duplicate-cu.exp: find index type, check type is valid
=== gdb Summary ===
# of expected passes 1
# of unexpected failures 2
# of unresolved testcases 1
I considered changing the code to build a local vector of units first,
then move it in per_bfd->all_units on success, that would avoid having
to clean it up on error. I did not do it because it's a much larger
change, but we could consider it.
Change-Id: I49bcc0cb4b34aba3d882b27c8a93c168e8875c08
Approved-By: Tom Tromey <tom@tromey.com>