http://sourceware.org/ml/gdb-patches/2015-10/msg00166.html Subject: [patch] Fix internal error on DW_OP_bregx(-1) --ibTvN161/egqYuK8 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Hi, 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. No regressions on {x86_64,x86_64-m32,i686}-fedorarawhide-linux-gnu. Jan --ibTvN161/egqYuK8 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline; filename="undefreg.patch" gdb/ChangeLog 2015-10-12 Jan Kratochvil * findvar.c (address_from_register): Check REGNUM validity. gdb/testsuite/ChangeLog 2015-10-12 Jan Kratochvil * gdb.dwarf2/dw2-regno-invalid.S: New file. * gdb.dwarf2/dw2-regno-invalid.exp: New file. 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/gdb.dwarf2/dw2-regno-invalid.S b/gdb/testsuite/gdb.dwarf2/dw2-regno-invalid.S new file mode 100644 index 0000000..075bfd6 --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/dw2-regno-invalid.S @@ -0,0 +1,91 @@ +/* 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 . */ + + .section .debug_info +debug_start: + .4byte debug_end - 1f /* Length of Compilation Unit Info */ +1: + .2byte 0x3 /* DWARF version number */ + .4byte .Ldebug_abbrev0 /* Offset Into Abbrev. Section */ + .byte 0x4 /* Pointer Size (in bytes) */ + .uleb128 0x1 /* (DIE (0xb) DW_TAG_compile_unit) */ + .ascii "clang-3.5.0-9.fc22.x86_64\0" /* DW_AT_producer */ + .byte 0x1 /* DW_AT_language */ + .ascii "1.c\0" /* DW_AT_name */ + .4byte main_label /* DW_AT_low_pc */ + .4byte main_label+0x10000 /* DW_AT_high_pc */ + + .uleb128 2 /* Abbrev: DW_TAG_subprogram */ + .byte 1 /* DW_AT_external */ + .ascii "main\0" /* DW_AT_name */ + .4byte main_label /* DW_AT_low_pc */ + .4byte main_label+0x10000 /* DW_AT_high_pc */ + + .uleb128 0x4 /* (DW_TAG_variable) */ + .ascii "variable\0" /* DW_AT_name */ + .2byte 2f - 1f /* DW_AT_location: DW_FORM_block2 */ +1: + .byte 0x92 /* DW_OP_bregx */ + .uleb128 0xffffffff + .sleb128 0 +2: + + .byte 0x0 /* end of children of main */ + .byte 0x0 /* end of children of CU */ +debug_end: + + .section .debug_abbrev +.Ldebug_abbrev0: + .uleb128 0x1 /* (abbrev code) */ + .uleb128 0x11 /* (TAG: DW_TAG_compile_unit) */ + .byte 0x1 /* DW_children_yes */ + .uleb128 0x25 /* (DW_AT_producer) */ + .uleb128 0x8 /* (DW_FORM_string) */ + .uleb128 0x13 /* (DW_AT_language) */ + .uleb128 0xb /* (DW_FORM_data1) */ + .uleb128 0x3 /* (DW_AT_name) */ + .uleb128 0x8 /* (DW_FORM_string) */ + .uleb128 0x11 /* DW_AT_low_pc */ + .uleb128 0x1 /* DW_FORM_addr */ + .uleb128 0x12 /* DW_AT_high_pc */ + .uleb128 0x1 /* DW_FORM_addr */ + .byte 0x0 + .byte 0x0 + + .uleb128 2 /* Abbrev code */ + .uleb128 0x2e /* DW_TAG_subprogram */ + .byte 1 /* has_children */ + .uleb128 0x3f /* DW_AT_external */ + .uleb128 0xc /* DW_FORM_flag */ + .uleb128 0x3 /* DW_AT_name */ + .uleb128 0x8 /* DW_FORM_string */ + .uleb128 0x11 /* DW_AT_low_pc */ + .uleb128 0x1 /* DW_FORM_addr */ + .uleb128 0x12 /* DW_AT_high_pc */ + .uleb128 0x1 /* DW_FORM_addr */ + .byte 0x0 /* Terminator */ + .byte 0x0 /* Terminator */ + + + .uleb128 0x4 /* (abbrev code) */ + .uleb128 0x34 /* (TAG: DW_TAG_variable) */ + .byte 0x0 /* DW_children_yes */ + .uleb128 0x3 /* (DW_AT_name) */ + .uleb128 0x8 /* (DW_FORM_string) */ + .uleb128 0x02 /* (DW_AT_location) */ + .uleb128 0x3 /* (DW_FORM_block2) */ + .byte 0x0 + .byte 0x0 + .byte 0x0 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..7c3a404 --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/dw2-regno-invalid.exp @@ -0,0 +1,32 @@ +# 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 + +# 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 + +if { [gdb_compile "${srcdir}/${subdir}/${srcfile} ${srcdir}/${subdir}/${srcfile2}" \ + "${binfile}" executable {}] != "" } { + return -1 +} + +clean_restart ${binfile} +runto_main + +gdb_test "p variable" --ibTvN161/egqYuK8--