[PATCH][gdb/symtab] Add symbol with inherited DW_AT_const_value to psymtabs
Tom de Vries
tdevries@suse.de
Tue Apr 7 11:59:22 GMT 2020
Hi,
Consider the test-case added in this patch, with resulting dwarf (related to
variable aaa):
...
<0><d2>: Abbrev Number: 2 (DW_TAG_partial_unit)
<1><eb>: Abbrev Number: 4 (DW_TAG_variable)
<ec> DW_AT_name : aaa
<f0> DW_AT_type : <0xe4>
<f4> DW_AT_const_value : 1
<0><10c>: Abbrev Number: 2 (DW_TAG_compile_unit)
<10e> DW_AT_name : <artificial>
<1><11b>: Abbrev Number: 3 (DW_TAG_variable)
<11c> DW_AT_abstract_origin: <0xeb>
...
When running the test-case, we see:
...
(gdb) p aaa^M
No symbol "aaa" in current context.^M
(gdb) FAIL: gdb.dwarf2/imported-unit-abstract-const-value.exp: p aaa
...
while with target board readnow.exp, we have:
...
(gdb) p aaa^M
$1 = 1^M
...
This is due to the fact that there's no aaa symbol in the partial symtabs:
...
Partial symtab for source file <artificial>@0x101 (object 0x351cf40)^M
...
Global partial symbols:^M
`main', function, 0x4004a7^M
^M
...
which is due to the fact that when attempting to add the symbol corresponding
to DIE 0x11b in add_partial_symbol:
...
(gdb) p /x pdi->sect_off
$4 = 0x11b
(gdb) p pdi.has_const_value
$5 = 0
...
it seems the DW_AT_const_value was not inherited from DIE 0xeb, and
consequently we leave without adding a partial symbol.
Fix this by making sure that partial_die_info::has_const_value is inherited
in partial_die_info::fixup.
Build and reg-tested on x86_64-linux.
Tested test-case with target boards readnow, cc-with-gdb-index and
cc-with-debug-names. The "print aaa" test fails for cc-with-gdb-index, that's
PR25791, the test passes when applying the corresponding proposed patch.
OK for trunk?
Thanks,
- Tom
[gdb/symtab] Add symbol with inherited DW_AT_const_value to psymtabs
gdb/ChangeLog:
2020-04-07 Tom de Vries <tdevries@suse.de>
PR symtab/25796
* dwarf2/read.c (partial_die_info::fixup): Inherit has_const_value.
gdb/testsuite/ChangeLog:
2020-04-07 Tom de Vries <tdevries@suse.de>
PR symtab/25796
* gdb.dwarf2/imported-unit-abstract-const-value.exp: New file.
---
gdb/dwarf2/read.c | 17 ++++
.../imported-unit-abstract-const-value.exp | 98 ++++++++++++++++++++++
2 files changed, 115 insertions(+)
diff --git a/gdb/dwarf2/read.c b/gdb/dwarf2/read.c
index 749acb3ba2..19df5e491e 100644
--- a/gdb/dwarf2/read.c
+++ b/gdb/dwarf2/read.c
@@ -18291,6 +18291,23 @@ partial_die_info::fixup (struct dwarf2_cu *cu)
}
}
+ if (!has_const_value && has_specification)
+ {
+ struct partial_die_info *spec_die;
+
+ auto res = find_partial_die (spec_offset, spec_is_dwz, cu);
+ spec_die = res.pdi;
+ cu = res.cu;
+
+ spec_die->fixup (cu);
+
+ if (spec_die->has_const_value)
+ {
+ /* Copy DW_AT_const_value attribute if it is set. */
+ has_const_value = spec_die->has_const_value;
+ }
+ }
+
/* Set default names for some unnamed DIEs. */
if (name == NULL && tag == DW_TAG_namespace)
diff --git a/gdb/testsuite/gdb.dwarf2/imported-unit-abstract-const-value.exp b/gdb/testsuite/gdb.dwarf2/imported-unit-abstract-const-value.exp
new file mode 100644
index 0000000000..f93dc12388
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/imported-unit-abstract-const-value.exp
@@ -0,0 +1,98 @@
+# Copyright 2020 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/>.
+
+# Test that a concrete var importing an abstract var using
+# DW_AT_abstract_origin inherits the DW_AT_const_value attribute.
+
+load_lib dwarf.exp
+
+# This test can only be run on targets which support DWARF-2 and use gas.
+if {![dwarf2_support]} {
+ return 0
+};
+
+standard_testfile main.c .S
+
+set executable ${testfile}
+set asm_file [standard_output_file ${srcfile2}]
+
+# We need to know the size of integer type in order
+# to write some of the debugging info we'd like to generate.
+if [prepare_for_testing "failed to prepare" ${testfile} ${srcfile}] {
+ return -1
+}
+
+# Create the DWARF.
+Dwarf::assemble $asm_file {
+ declare_labels cu_label main_label int_label
+ declare_labels aaa_label
+ set int_size [get_sizeof "int" 4]
+
+ global srcdir subdir srcfile
+
+ extern main
+
+ set main_range [function_range main ${srcdir}/${subdir}/${srcfile}]
+ set main_start [lindex $main_range 0]
+ set main_length [lindex $main_range 1]
+
+ cu {} {
+ cu_label: partial_unit {
+ {language @DW_LANG_C}
+ {name "imported_unit.c"}
+ } {
+ int_label: base_type {
+ {byte_size $int_size sdata}
+ {encoding @DW_ATE_signed}
+ {name int}
+ }
+
+ aaa_label: DW_TAG_variable {
+ {name aaa}
+ {type :$int_label}
+ {const_value 1 DW_FORM_sdata}
+ }
+
+ main_label: subprogram {
+ {name main}
+ {type :$int_label}
+ {external 1 flag}
+ }
+ }
+ }
+
+ cu {} {
+ compile_unit {
+ {language @DW_LANG_C}
+ {name "<artificial>"}
+ } {
+ DW_TAG_variable {
+ {abstract_origin %$aaa_label}
+ }
+ subprogram {
+ {abstract_origin %$main_label}
+ {low_pc $main_start addr}
+ {high_pc "$main_start + $main_length" addr}
+ }
+ }
+ }
+}
+
+if { [prepare_for_testing "failed to prepare" ${testfile} \
+ [list $srcfile $asm_file] {nodebug}] } {
+ return -1
+}
+
+gdb_test "p aaa" "= 1"
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