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[binutils-gdb] Fix internal error on DW_OP_bregx(-1)
- From: Jan Kratochvil <jkratoch at sourceware dot org>
- To: gdb-cvs at sourceware dot org
- Date: 20 Oct 2015 18:42:10 -0000
- Subject: [binutils-gdb] Fix internal error on DW_OP_bregx(-1)
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=5f3ff4f893d7d70f79cb2daf4001be7047cd126b
commit 5f3ff4f893d7d70f79cb2daf4001be7047cd126b
Author: Jan Kratochvil <jan.kratochvil@redhat.com>
Date: Tue Oct 20 20:40:38 2015 +0200
Fix internal error on DW_OP_bregx(-1)
https://bugzilla.redhat.com/show_bug.cgi?id=1270564#c15
https://bugzilla.redhat.com/attachment.cgi?id=1081772
clang-3.5.0-9.fc22.x86_64
<3><22b2>: Abbrev Number: 69 (DW_TAG_variable)
<22b3> DW_AT_location : 7 byte block: 92 ff ff ff ff f 0 (DW_OP_bregx: 4294967295 (r-1) 0)
<22bb> DW_AT_name : (indirect string, offset: 0x2a36): texture_data
<22c1> DW_AT_type : <0x1d3>
(gdb) p variable
warning: Unmapped DWARF Register #-1 encountered.
regcache.c:177: internal-error: register_size: Assertion `regnum >= 0 && regnum < (gdbarch_num_regs (gdbarch) + gdbarch_num_pseudo_regs
(gdbarch))' failed.
[...]
Quit this debugging session? (y or n) FAIL: gdb.dwarf2/dw2-regno-invalid.exp: p variable (GDB internal error)
-> (x86_64)
(gdb) p variable
warning: Unmapped DWARF Register #-1 encountered.
Invalid register #-1, expecting 0 <= # < 220
(gdb) PASS: gdb.dwarf2/dw2-regno-invalid.exp: p variable
-> (i386)
(gdb) p variable
Invalid register #104, expecting 0 <= # < 104
(gdb) PASS: gdb.dwarf2/dw2-regno-invalid.exp: p variable
GDB calls gdbarch_dwarf2_reg_to_regnum() first which returns -1 in the x86_64
case
if (regnum == -1)
warning (_("Unmapped DWARF Register #%d encountered."), reg);
but in i386 case it does:
/* This will hopefully provoke a warning. */
return gdbarch_num_regs (gdbarch) + gdbarch_num_pseudo_regs (gdbarch);
and the default implementation is a nop, leaving whatever register number
the DWARF specified.
gdb/ChangeLog
2015-10-20 Jan Kratochvil <jan.kratochvil@redhat.com>
* findvar.c (address_from_register): Check REGNUM validity.
gdb/testsuite/ChangeLog
2015-10-20 Jan Kratochvil <jan.kratochvil@redhat.com>
Pedro Alves <palves@redhat.com>
* gdb.dwarf2/dw2-regno-invalid.exp: New file.
* lib/dwarf.exp (Dwarf): Add DW_OP_bregx.
Diff:
---
gdb/ChangeLog | 4 ++
gdb/findvar.c | 6 +++
gdb/testsuite/ChangeLog | 6 +++
gdb/testsuite/gdb.dwarf2/dw2-regno-invalid.exp | 71 ++++++++++++++++++++++++++
gdb/testsuite/lib/dwarf.exp | 5 ++
5 files changed, 92 insertions(+)
diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index b934297..e546950 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,7 @@
+2015-10-20 Jan Kratochvil <jan.kratochvil@redhat.com>
+
+ * findvar.c (address_from_register): Check REGNUM validity.
+
2015-10-20 Aleksandar Ristovski <aristovski@qnx.com>
* gdb/nto-procfs.c (procfs_pid_to_exec_file): New function.
diff --git a/gdb/findvar.c b/gdb/findvar.c
index 0f46e53..855947d 100644
--- a/gdb/findvar.c
+++ b/gdb/findvar.c
@@ -927,6 +927,12 @@ address_from_register (int regnum, struct frame_info *frame)
struct type *type = builtin_type (gdbarch)->builtin_data_ptr;
struct value *value;
CORE_ADDR result;
+ int regnum_max_excl = (gdbarch_num_regs (gdbarch)
+ + gdbarch_num_pseudo_regs (gdbarch));
+
+ if (regnum < 0 || regnum >= regnum_max_excl)
+ error (_("Invalid register #%d, expecting 0 <= # < %d"), regnum,
+ regnum_max_excl);
/* This routine may be called during early unwinding, at a time
where the ID of FRAME is not yet known. Calling value_from_register
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 8a8f132..bf63b5d 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2015-10-20 Jan Kratochvil <jan.kratochvil@redhat.com>
+ Pedro Alves <palves@redhat.com>
+
+ * gdb.dwarf2/dw2-regno-invalid.exp: New file.
+ * lib/dwarf.exp (Dwarf): Add DW_OP_bregx.
+
2015-10-19 Josh Stone <jistone@redhat.com>
* gdb.base/catch-syscall.c: Include <sched.h>.
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-regno-invalid.exp b/gdb/testsuite/gdb.dwarf2/dw2-regno-invalid.exp
new file mode 100644
index 0000000..a7d77c5
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-regno-invalid.exp
@@ -0,0 +1,71 @@
+# Copyright 2015 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 GDB does not internal error on DWARF register number -1 which is invalid
+# in DWARF. clang-3.5.0-9.fc22.x86_64 produced it inside DW_AT_location.
+
+# This test can only be run on targets which support DWARF-2 and use gas.
+if {![dwarf2_support]} {
+ return 0
+}
+
+standard_testfile .S main.c
+
+# Make some DWARF for the test.
+set asm_file [standard_output_file $srcfile]
+Dwarf::assemble $asm_file {
+ cu {} {
+ compile_unit {
+ {low_pc main DW_FORM_addr}
+ {high_pc main+0x10000 DW_FORM_addr}
+ } {
+ declare_labels integer_label
+
+ integer_label: DW_TAG_base_type {
+ {DW_AT_byte_size 4 DW_FORM_sdata}
+ {DW_AT_encoding @DW_ATE_signed}
+ {DW_AT_name integer}
+ }
+
+ DW_TAG_subprogram {
+ {name main}
+ {DW_AT_external 1 flag}
+ {low_pc main DW_FORM_addr}
+ {high_pc main+0x10000 DW_FORM_addr}
+ } {
+ DW_TAG_variable {
+ {DW_AT_name bregx}
+ {DW_AT_type :$integer_label}
+ {DW_AT_external 1 flag}
+ {DW_AT_location {
+ DW_OP_bregx 0xffffffff 0
+ } SPECIAL_expr}
+ }
+ }
+ }
+ }
+}
+
+if { [prepare_for_testing ${testfile}.exp ${testfile} \
+ [list $srcfile2 $asm_file] {nodebug}] } {
+ return -1
+}
+
+runto_main
+
+# Variable 'bregx' needs to be inside main as for global symbols GDB does not
+# support non-trivial DW_AT_location. Former GDB printed internal error here.
+gdb_test "p bregx"
diff --git a/gdb/testsuite/lib/dwarf.exp b/gdb/testsuite/lib/dwarf.exp
index 515334e..888ba94 100644
--- a/gdb/testsuite/lib/dwarf.exp
+++ b/gdb/testsuite/lib/dwarf.exp
@@ -901,6 +901,11 @@ namespace eval Dwarf {
_op .byte [lindex $line 1]
}
+ DW_OP_bregx {
+ _op .uleb128 [lindex $line 1]
+ _op .sleb128 [lindex $line 2]
+ }
+
default {
if {[llength $line] > 1} {
error "Unimplemented: operands in location for $opcode"