[gdb] Fix segv in "maint print symbols" for ada exec

When using the executable from test-case gdb.ada/access_to_packed_array.exp
(read-in using -readnow) and printing the symbols using "maint print symbols",
we run into a segv:
...
$ gdb -readnow -batch access_to_packed_array/foo -ex "maint print symbols"
   ...
     info: array (<>) of character; computed at runtime
     ptr: range 0 .. 2147483647; computed at runtime
Aborted (core dumped)
...

What happens is that dwarf2_evaluate_property gets called and sets the local
frame variable to the current frame, which happens to be NULL.  Subsequently
the PROP_LOCLIST handling code is executed, where get_frame_address_in_block
gets called with argument NULL, and the segv is triggered.

Fix this by handling a NULL frame in the PROP_LOCLIST handling code in
dwarf2_evaluate_property.

Build and reg-tested on x86_64-linux.

gdb/ChangeLog:

2020-03-11  Tom de Vries  <tdevries@suse.de>

	* dwarf2/loc.c (dwarf2_evaluate_property): Handle NULL frame in
	PROP_LOCLIST handling code.

gdb/testsuite/ChangeLog:

2020-03-11  Tom de Vries  <tdevries@suse.de>

	* gdb.ada/access_to_packed_array.exp: Test printing of expanded
	symtabs.
This commit is contained in:
Tom de Vries 2020-03-11 00:30:54 +01:00
parent 8c95582da8
commit 1c33af7764
4 changed files with 25 additions and 1 deletions

View File

@ -1,3 +1,8 @@
2020-03-11 Tom de Vries <tdevries@suse.de>
* dwarf2/loc.c (dwarf2_evaluate_property): Handle NULL frame in
PROP_LOCLIST handling code.
2020-03-10 Andrew Burgess <andrew.burgess@embecosm.com>
* buildsym-legacy.c (record_line): Pass extra parameter to

View File

@ -2511,11 +2511,15 @@ dwarf2_evaluate_property (const struct dynamic_prop *prop,
{
struct dwarf2_property_baton *baton
= (struct dwarf2_property_baton *) prop->data.baton;
CORE_ADDR pc = get_frame_address_in_block (frame);
CORE_ADDR pc;
const gdb_byte *data;
struct value *val;
size_t size;
if (frame == NULL
|| !get_frame_address_in_block_if_available (frame, &pc))
return false;
data = dwarf2_find_location_expression (&baton->loclist, &size, pc);
if (data != NULL)
{

View File

@ -1,3 +1,8 @@
2020-03-11 Tom de Vries <tdevries@suse.de>
* gdb.ada/access_to_packed_array.exp: Test printing of expanded
symtabs.
2020-03-10 Andrew Burgess <andrew.burgess@embecosm.com>
Bernd Edlinger <bernd.edlinger@hotmail.de>

View File

@ -23,6 +23,16 @@ if {[gdb_compile_ada "${srcfile}" "${binfile}" executable [list debug]] != "" }
clean_restart ${testfile}
# Test that printing symbols does not cause segv.
gdb_test_no_output "maint expand-symtabs"
set file [standard_output_file gdb.txt]
gdb_test_no_output "set logging file $file" "set logging file"
gdb_test_no_output "set logging redirect on"
gdb_test "set logging on"
gdb_test_no_output "maint print symbols"
gdb_test "set logging off"
file delete $file
set bp_location [gdb_get_line_number "BREAK" ${testdir}/foo.adb]
runto "foo.adb:$bp_location"