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[PATCH] Handle DW_AT_ranges when reading partial symtabs
- From: Tom Tromey <tromey at adacore dot com>
- To: gdb-patches at sourceware dot org
- Cc: Tom Tromey <tromey at adacore dot com>
- Date: Fri, 29 Mar 2019 14:00:30 -0600
- Subject: [PATCH] Handle DW_AT_ranges when reading partial symtabs
add_partial_subprogram does not handle DW_AT_ranges, while the full
symtab reader does. This can lead to discrepancies where a function
is not put into a partial symtab, and so is not available to "break"
and the like -- but is available if the full symtab has somehow been
read.
This patch fixes the bug by arranging to read DW_AT_ranges when
reading partial DIEs.
This is PR symtab/23331.
The new test case is derived from dw2-ranges-func.exp, which is why I
kept the copyright dates.
gdb/ChangeLog
2019-03-29 Tom Tromey <tromey@adacore.com>
PR symtab/23331:
* dwarf2read.c (partial_die_info::read): Handle DW_AT_ranges.
gdb/testsuite/ChangeLog
2019-03-29 Tom Tromey <tromey@adacore.com>
PR symtab/23331:
* gdb.dwarf2/dw2-ranges-main.c: New file.
* gdb.dwarf2/dw2-ranges-psym.c: New file.
* gdb.dwarf2/dw2-ranges-psym.exp: New file.
---
gdb/ChangeLog | 5 +
gdb/dwarf2read.c | 19 +++
gdb/testsuite/ChangeLog | 7 +
gdb/testsuite/gdb.dwarf2/dw2-ranges-main.c | 19 +++
gdb/testsuite/gdb.dwarf2/dw2-ranges-psym.c | 46 +++++++
gdb/testsuite/gdb.dwarf2/dw2-ranges-psym.exp | 134 +++++++++++++++++++
6 files changed, 230 insertions(+)
create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-ranges-main.c
create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-ranges-psym.c
create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-ranges-psym.exp
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 658c86264bf..a5e953bd427 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -18751,6 +18751,25 @@ partial_die_info::read (const struct die_reader_specs *reader,
main_subprogram = DW_UNSND (&attr);
break;
+ case DW_AT_ranges:
+ {
+ /* It would be nice to reuse dwarf2_get_pc_bounds here,
+ but that requires a full DIE, so instead we just
+ reimplement it. */
+ int need_ranges_base = tag != DW_TAG_compile_unit;
+ unsigned int ranges_offset = (DW_UNSND (&attr)
+ + (need_ranges_base
+ ? cu->ranges_base
+ : 0));
+
+ /* Value of the DW_AT_ranges attribute is the offset in the
+ .debug_ranges section. */
+ if (dwarf2_ranges_read (ranges_offset, &lowpc, &highpc, cu,
+ nullptr))
+ has_pc_info = 1;
+ }
+ break;
+
default:
break;
}
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-ranges-main.c b/gdb/testsuite/gdb.dwarf2/dw2-ranges-main.c
new file mode 100644
index 00000000000..35a4d4c07e1
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-ranges-main.c
@@ -0,0 +1,19 @@
+/* Copyright 2019 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/>. */
+
+int main ()
+{
+ return 0;
+}
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-ranges-psym.c b/gdb/testsuite/gdb.dwarf2/dw2-ranges-psym.c
new file mode 100644
index 00000000000..7d0408a56a9
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-ranges-psym.c
@@ -0,0 +1,46 @@
+/* Copyright 2018-2019 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/>. */
+
+volatile int e = 0;
+
+void
+baz (void)
+{
+ asm ("baz_label: .globl baz_label");
+} /* baz end */
+
+void
+foo_low (void)
+{ /* foo_low prologue */
+ asm ("foo_low_label: .globl foo_low_label");
+ baz (); /* foo_low baz call */
+ asm ("foo_low_label2: .globl foo_low_label2");
+} /* foo_low end */
+
+void
+bar (void)
+{
+ asm ("bar_label: .globl bar_label");
+} /* bar end */
+
+void
+foo (void)
+{ /* foo prologue */
+ asm ("foo_label: .globl foo_label");
+ bar (); /* foo bar call */
+ asm ("foo_label2: .globl foo_label2");
+ if (e) foo_low (); /* foo foo_low call */
+ asm ("foo_label3: .globl foo_label3");
+} /* foo end */
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-ranges-psym.exp b/gdb/testsuite/gdb.dwarf2/dw2-ranges-psym.exp
new file mode 100644
index 00000000000..eb1130a2238
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-ranges-psym.exp
@@ -0,0 +1,134 @@
+# Copyright 2018-2019 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/>.
+
+load_lib dwarf.exp
+
+# Test that psymbols are made when DW_AT_ranges is used.
+
+# This test can only be run on targets which support DWARF-2 and use gas.
+if {![dwarf2_support]} {
+ unsupported "dwarf2 support required for this test"
+ return 0
+}
+
+if [get_compiler_info] {
+ return -1
+}
+if !$gcc_compiled {
+ unsupported "gcc required for this test"
+ return 0
+}
+
+standard_testfile dw2-ranges-main.c dw2-ranges-psym.c dw2-ranges-psym-dw.S
+
+# We need to know the size of integer and address types in order to
+# write some of the debugging info we'd like to generate.
+#
+# For that, we ask GDB by debugging our test program. Any program
+# would do, but since we already have it specifically for this
+# testcase, might as well use that.
+
+if { [prepare_for_testing "failed to prepare" ${testfile} \
+ [list ${srcfile} ${srcfile2}]] } {
+ return -1
+}
+
+set asm_file [standard_output_file $srcfile3]
+Dwarf::assemble $asm_file {
+ global srcdir subdir srcfile srcfile2
+ declare_labels integer_label volatile_label func_ranges_label cu_ranges_label
+ set int_size [get_sizeof "int" 4]
+
+ # Find start address and length for our functions.
+ set sources [list ${srcdir}/${subdir}/$srcfile ${srcdir}/${subdir}/$srcfile2]
+ lassign [function_range foo $sources] \
+ foo_start foo_len
+ set foo_end "$foo_start + $foo_len"
+ lassign [function_range foo_low $sources] \
+ foo_low_start foo_low_len
+ set foo_low_end "$foo_low_start + $foo_low_len"
+ lassign [function_range bar $sources] \
+ bar_start bar_len
+ set bar_end "$bar_start + $bar_len"
+ lassign [function_range baz $sources] \
+ baz_start baz_len
+ set baz_end "$baz_start + $baz_len"
+
+ cu {} {
+ compile_unit {
+ {language @DW_LANG_C}
+ {name dw-ranges-psym.c}
+ {low_pc 0 addr}
+ {ranges ${cu_ranges_label} DW_FORM_sec_offset}
+ } {
+ integer_label: DW_TAG_base_type {
+ {DW_AT_byte_size $int_size DW_FORM_sdata}
+ {DW_AT_encoding @DW_ATE_signed}
+ {DW_AT_name integer}
+ }
+ volatile_label: DW_TAG_volatile_type {
+ {type :$integer_label}
+ }
+ subprogram {
+ {external 1 flag}
+ {name someothername}
+ {ranges ${func_ranges_label} DW_FORM_sec_offset}
+ }
+ subprogram {
+ {external 1 flag}
+ {name bar}
+ {low_pc $bar_start addr}
+ {high_pc $bar_len DW_FORM_data4}
+ }
+ subprogram {
+ {external 1 flag}
+ {name baz}
+ {low_pc $baz_start addr}
+ {high_pc $baz_len DW_FORM_data4}
+ }
+ }
+ }
+
+ # Generate ranges data.
+ ranges {is_64 [is_64_target]} {
+ func_ranges_label: sequence {
+ {range {$foo_start } $foo_end}
+ {range {$foo_low_start} $foo_low_end}
+ }
+ cu_ranges_label: sequence {
+ {range {$foo_start } $foo_end}
+ {range {$foo_low_start} $foo_low_end}
+ {range {$bar_start} $bar_end}
+ {range {$baz_start} $baz_end}
+ }
+ }
+}
+
+if { [prepare_for_testing "failed to prepare" ${testfile} \
+ [list $srcfile $srcfile2 $asm_file] {nodebug}] } {
+ return -1
+}
+
+if ![runto_main] {
+ return -1
+}
+
+# "someothername" should be put into the partial symbol table, but
+# there was a bug causing functions using DW_AT_ranges not to be.
+# Note we use a name that is very different from the linkage name, in
+# order to not set the breakpoint via minsyms.
+gdb_test "break someothername" \
+ "Breakpoint.*at.*" \
+ "break someothername"
--
2.20.1