From 5f3ff4f893d7d70f79cb2daf4001be7047cd126b Mon Sep 17 00:00:00 2001 From: Jan Kratochvil Date: Tue, 20 Oct 2015 20:40:38 +0200 Subject: [PATCH] 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 * findvar.c (address_from_register): Check REGNUM validity. gdb/testsuite/ChangeLog 2015-10-20 Jan Kratochvil Pedro Alves * gdb.dwarf2/dw2-regno-invalid.exp: New file. * lib/dwarf.exp (Dwarf): Add DW_OP_bregx. --- 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(+) create mode 100644 gdb/testsuite/gdb.dwarf2/dw2-regno-invalid.exp 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 + + * findvar.c (address_from_register): Check REGNUM validity. + 2015-10-20 Aleksandar Ristovski * 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 + Pedro Alves + + * gdb.dwarf2/dw2-regno-invalid.exp: New file. + * lib/dwarf.exp (Dwarf): Add DW_OP_bregx. + 2015-10-19 Josh Stone * gdb.base/catch-syscall.c: Include . 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 . +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" -- 2.7.4