RFC: fix PR c++/14999
Tom Tromey
tromey@redhat.com
Tue Jan 8 17:11:00 GMT 2013
This fixes PR c++/14999.
The problem here is that setting a tracepoint and collecting a certain
local variable will cause a crash, if the source code was compiled with
clang.
The bug is just a missing call to require_rvalue when handling
DW_OP_fbreg in the DWARF->AX translator.
This patch includes a test case which is assembly created by clang, then
lightly hacked by me (to change the file and directory names). I think
this is ok, since the original source file is so small; but if you
disagree let me know.
Built and regtested on x86-64 Fedora 16.
Tom
PR c++/14999:
* dwarf2loc.c (dwarf2_compile_expr_to_ax) <DW_OP_fbreg>:
Call require_rvalue.
* gdb.dwarf2/trace-crash.s: New file.
* gdb.dwarf2/trace-crash.exp: New file.
diff --git a/gdb/dwarf2loc.c b/gdb/dwarf2loc.c
index 33300ee..2282feb 100644
--- a/gdb/dwarf2loc.c
+++ b/gdb/dwarf2loc.c
@@ -2878,6 +2878,7 @@ dwarf2_compile_expr_to_ax (struct agent_expr *expr, struct axs_value *loc,
op_ptr = safe_read_sleb128 (op_ptr, op_end, &offset);
dwarf2_compile_expr_to_ax (expr, loc, arch, addr_size, datastart,
datastart + datalen, per_cu);
+ require_rvalue (expr, loc);
if (offset != 0)
{
diff --git a/gdb/testsuite/gdb.dwarf2/trace-crash.S b/gdb/testsuite/gdb.dwarf2/trace-crash.S
new file mode 100644
index 0000000..3a9a771
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/trace-crash.S
@@ -0,0 +1,295 @@
+/* This file was created using Clang -g -S from this source
+ code:
+
+ int func(int p) {
+ int x = p + 3;
+ return x;
+ }
+
+ int main() { return func(3); }
+
+ See http://sourceware.org/bugzilla/show_bug.cgi?id=14999
+*/
+
+ .file "trace-crash.c"
+ .file 1 "trace-crash.c"
+ .text
+ .globl func
+ .align 16, 0x90
+ .type func,@function
+func: # @func
+ .cfi_startproc
+.Lfunc_begin0:
+ .loc 1 1 0 # trace-crash.c:1:0
+# BB#0: # %entry
+ movl %edi, -4(%rsp)
+ .loc 1 2 0 prologue_end # trace-crash.c:2:0
+.Ltmp0:
+ movl -4(%rsp), %edi
+ addl $3, %edi
+ movl %edi, -8(%rsp)
+ .loc 1 3 0 # trace-crash.c:3:0
+ movl -8(%rsp), %eax
+ ret
+.Ltmp1:
+.Ltmp2:
+ .size func, .Ltmp2-func
+.Lfunc_end0:
+ .cfi_endproc
+
+ .globl main
+ .align 16, 0x90
+ .type main,@function
+main: # @main
+ .cfi_startproc
+.Lfunc_begin1:
+ .loc 1 6 0 # trace-crash.c:6:0
+# BB#0: # %entry
+ pushq %rbp
+.Ltmp5:
+ .cfi_def_cfa_offset 16
+.Ltmp6:
+ .cfi_offset %rbp, -16
+ movq %rsp, %rbp
+.Ltmp7:
+ .cfi_def_cfa_register %rbp
+ subq $16, %rsp
+ movl $3, %edi
+ movl $0, -4(%rbp)
+ .loc 1 6 0 prologue_end # trace-crash.c:6:0
+.Ltmp8:
+ callq func
+ addq $16, %rsp
+ popq %rbp
+ ret
+.Ltmp9:
+.Ltmp10:
+ .size main, .Ltmp10-main
+.Lfunc_end1:
+ .cfi_endproc
+
+.Ltext_end:
+ .data
+.Ldata_end:
+ .text
+.Lsection_end1:
+ .section .debug_info,"",@progbits
+.Lsection_info:
+ .section .debug_abbrev,"",@progbits
+.Lsection_abbrev:
+ .section .debug_aranges,"",@progbits
+ .section .debug_macinfo,"",@progbits
+ .section .debug_line,"",@progbits
+.Lsection_line:
+ .section .debug_loc,"",@progbits
+ .section .debug_pubtypes,"",@progbits
+ .section .debug_str,"MS",@progbits,1
+.Linfo_string:
+ .section .debug_ranges,"",@progbits
+.Ldebug_range:
+ .section .debug_loc,"",@progbits
+.Lsection_debug_loc:
+ .text
+.Ltext_begin:
+ .data
+ .section .debug_info,"",@progbits
+.L.debug_info_begin0:
+ .long 147 # Length of Compilation Unit Info
+ .short 2 # DWARF version number
+ .long .L.debug_abbrev_begin # Offset Into Abbrev. Section
+ .byte 8 # Address Size (in bytes)
+ .byte 1 # Abbrev [1] 0xb:0x8c DW_TAG_compile_unit
+ .long .Linfo_string0 # DW_AT_producer
+ .short 12 # DW_AT_language
+ .long .Linfo_string1 # DW_AT_name
+ .quad 0 # DW_AT_low_pc
+ .long .Lsection_line # DW_AT_stmt_list
+ .long .Linfo_string2 # DW_AT_comp_dir
+ .byte 2 # Abbrev [2] 0x26:0x4c DW_TAG_subprogram
+ .long .Linfo_string3 # DW_AT_name
+ .byte 1 # DW_AT_decl_file
+ .byte 1 # DW_AT_decl_line
+ # DW_AT_prototyped
+ .long 114 # DW_AT_type
+ # DW_AT_external
+ .quad .Lfunc_begin0 # DW_AT_low_pc
+ .quad .Lfunc_end0 # DW_AT_high_pc
+ .byte 1 # DW_AT_frame_base
+ .byte 87
+ # DW_AT_APPLE_omit_frame_ptr
+ .byte 3 # Abbrev [3] 0x43:0xe DW_TAG_formal_parameter
+ .long .Linfo_string6 # DW_AT_name
+ .byte 1 # DW_AT_decl_file
+ .byte 1 # DW_AT_decl_line
+ .long 114 # DW_AT_type
+ .byte 2 # DW_AT_location
+ .byte 145
+ .byte 124
+ .byte 4 # Abbrev [4] 0x51:0x20 DW_TAG_lexical_block
+ .quad .Ltmp0 # DW_AT_low_pc
+ .quad .Ltmp1 # DW_AT_high_pc
+ .byte 5 # Abbrev [5] 0x62:0xe DW_TAG_variable
+ .long .Linfo_string7 # DW_AT_name
+ .byte 1 # DW_AT_decl_file
+ .byte 2 # DW_AT_decl_line
+ .long 114 # DW_AT_type
+ .byte 2 # DW_AT_location
+ .byte 145
+ .byte 120
+ .byte 0 # End Of Children Mark
+ .byte 0 # End Of Children Mark
+ .byte 6 # Abbrev [6] 0x72:0x7 DW_TAG_base_type
+ .long .Linfo_string4 # DW_AT_name
+ .byte 5 # DW_AT_encoding
+ .byte 4 # DW_AT_byte_size
+ .byte 7 # Abbrev [7] 0x79:0x1d DW_TAG_subprogram
+ .long .Linfo_string5 # DW_AT_name
+ .byte 1 # DW_AT_decl_file
+ .byte 6 # DW_AT_decl_line
+ .long 114 # DW_AT_type
+ # DW_AT_external
+ .quad .Lfunc_begin1 # DW_AT_low_pc
+ .quad .Lfunc_end1 # DW_AT_high_pc
+ .byte 1 # DW_AT_frame_base
+ .byte 86
+ .byte 0 # End Of Children Mark
+.L.debug_info_end0:
+ .section .debug_abbrev,"",@progbits
+.L.debug_abbrev_begin:
+ .byte 1 # Abbreviation Code
+ .byte 17 # DW_TAG_compile_unit
+ .byte 1 # DW_CHILDREN_yes
+ .byte 37 # DW_AT_producer
+ .byte 14 # DW_FORM_strp
+ .byte 19 # DW_AT_language
+ .byte 5 # DW_FORM_data2
+ .byte 3 # DW_AT_name
+ .byte 14 # DW_FORM_strp
+ .byte 17 # DW_AT_low_pc
+ .byte 1 # DW_FORM_addr
+ .byte 16 # DW_AT_stmt_list
+ .byte 6 # DW_FORM_data4
+ .byte 27 # DW_AT_comp_dir
+ .byte 14 # DW_FORM_strp
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 2 # Abbreviation Code
+ .byte 46 # DW_TAG_subprogram
+ .byte 1 # DW_CHILDREN_yes
+ .byte 3 # DW_AT_name
+ .byte 14 # DW_FORM_strp
+ .byte 58 # DW_AT_decl_file
+ .byte 11 # DW_FORM_data1
+ .byte 59 # DW_AT_decl_line
+ .byte 11 # DW_FORM_data1
+ .byte 39 # DW_AT_prototyped
+ .byte 25 # DW_FORM_flag_present
+ .byte 73 # DW_AT_type
+ .byte 19 # DW_FORM_ref4
+ .byte 63 # DW_AT_external
+ .byte 25 # DW_FORM_flag_present
+ .byte 17 # DW_AT_low_pc
+ .byte 1 # DW_FORM_addr
+ .byte 18 # DW_AT_high_pc
+ .byte 1 # DW_FORM_addr
+ .byte 64 # DW_AT_frame_base
+ .byte 10 # DW_FORM_block1
+ .ascii "\347\177" # DW_AT_APPLE_omit_frame_ptr
+ .byte 25 # DW_FORM_flag_present
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 3 # Abbreviation Code
+ .byte 5 # DW_TAG_formal_parameter
+ .byte 0 # DW_CHILDREN_no
+ .byte 3 # DW_AT_name
+ .byte 14 # DW_FORM_strp
+ .byte 58 # DW_AT_decl_file
+ .byte 11 # DW_FORM_data1
+ .byte 59 # DW_AT_decl_line
+ .byte 11 # DW_FORM_data1
+ .byte 73 # DW_AT_type
+ .byte 19 # DW_FORM_ref4
+ .byte 2 # DW_AT_location
+ .byte 10 # DW_FORM_block1
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 4 # Abbreviation Code
+ .byte 11 # DW_TAG_lexical_block
+ .byte 1 # DW_CHILDREN_yes
+ .byte 17 # DW_AT_low_pc
+ .byte 1 # DW_FORM_addr
+ .byte 18 # DW_AT_high_pc
+ .byte 1 # DW_FORM_addr
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 5 # Abbreviation Code
+ .byte 52 # DW_TAG_variable
+ .byte 0 # DW_CHILDREN_no
+ .byte 3 # DW_AT_name
+ .byte 14 # DW_FORM_strp
+ .byte 58 # DW_AT_decl_file
+ .byte 11 # DW_FORM_data1
+ .byte 59 # DW_AT_decl_line
+ .byte 11 # DW_FORM_data1
+ .byte 73 # DW_AT_type
+ .byte 19 # DW_FORM_ref4
+ .byte 2 # DW_AT_location
+ .byte 10 # DW_FORM_block1
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 6 # Abbreviation Code
+ .byte 36 # DW_TAG_base_type
+ .byte 0 # DW_CHILDREN_no
+ .byte 3 # DW_AT_name
+ .byte 14 # DW_FORM_strp
+ .byte 62 # DW_AT_encoding
+ .byte 11 # DW_FORM_data1
+ .byte 11 # DW_AT_byte_size
+ .byte 11 # DW_FORM_data1
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 7 # Abbreviation Code
+ .byte 46 # DW_TAG_subprogram
+ .byte 0 # DW_CHILDREN_no
+ .byte 3 # DW_AT_name
+ .byte 14 # DW_FORM_strp
+ .byte 58 # DW_AT_decl_file
+ .byte 11 # DW_FORM_data1
+ .byte 59 # DW_AT_decl_line
+ .byte 11 # DW_FORM_data1
+ .byte 73 # DW_AT_type
+ .byte 19 # DW_FORM_ref4
+ .byte 63 # DW_AT_external
+ .byte 25 # DW_FORM_flag_present
+ .byte 17 # DW_AT_low_pc
+ .byte 1 # DW_FORM_addr
+ .byte 18 # DW_AT_high_pc
+ .byte 1 # DW_FORM_addr
+ .byte 64 # DW_AT_frame_base
+ .byte 10 # DW_FORM_block1
+ .byte 0 # EOM(1)
+ .byte 0 # EOM(2)
+ .byte 0 # EOM(3)
+.L.debug_abbrev_end:
+ .section .debug_aranges,"",@progbits
+ .section .debug_ranges,"",@progbits
+ .section .debug_macinfo,"",@progbits
+ .section .debug_str,"MS",@progbits,1
+.Linfo_string0:
+ .asciz "clang version 3.3 "
+.Linfo_string1:
+ .asciz "trace-crash.c"
+.Linfo_string2:
+ .asciz "/tmp"
+.Linfo_string3:
+ .asciz "func"
+.Linfo_string4:
+ .asciz "int"
+.Linfo_string5:
+ .asciz "main"
+.Linfo_string6:
+ .asciz "p"
+.Linfo_string7:
+ .asciz "x"
+
+ .section ".note.GNU-stack","",@progbits
diff --git a/gdb/testsuite/gdb.dwarf2/trace-crash.exp b/gdb/testsuite/gdb.dwarf2/trace-crash.exp
new file mode 100644
index 0000000..7331868
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/trace-crash.exp
@@ -0,0 +1,41 @@
+# Copyright 2013 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
+load_lib trace-support.exp
+
+# This test can only be run on targets which support DWARF-2 and use gas.
+if {![dwarf2_support]} {
+ return 0
+}
+
+# This test can only be run on x86-64 targets.
+if {![istarget x86_64-*] || ![is_lp64_target]} {
+ return 0
+}
+
+standard_testfile .S
+
+if {[prepare_for_testing "${testfile}.exp" "${testfile}" ${testfile}.S \
+ nodebug]} {
+ return -1
+}
+
+gdb_test "trace ${testfile}.c:3" "Tracepoint $decimal .*" \
+ "set tracepoint"
+
+# This is a regression test for a crash when converting a DWARF
+# expression to AX.
+gdb_trace_setactions "set tracepoint actions" "" "collect x" "^$"
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