From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 30331 invoked by alias); 2 Jun 2011 20:12:37 -0000 Received: (qmail 30301 invoked by uid 22791); 2 Jun 2011 20:12:33 -0000 X-SWARE-Spam-Status: No, hits=-6.4 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_HI,SPF_HELO_PASS,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Thu, 02 Jun 2011 20:12:14 +0000 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p52KCE60028907 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Thu, 2 Jun 2011 16:12:14 -0400 Received: from host1.jankratochvil.net (ovpn-113-38.phx2.redhat.com [10.3.113.38]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id p52KCC66017186 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 2 Jun 2011 16:12:13 -0400 Received: from host1.jankratochvil.net (localhost [127.0.0.1]) by host1.jankratochvil.net (8.14.4/8.14.4) with ESMTP id p52KCBdc032591; Thu, 2 Jun 2011 22:12:11 +0200 Received: (from jkratoch@localhost) by host1.jankratochvil.net (8.14.4/8.14.4/Submit) id p52KCAQR032585; Thu, 2 Jun 2011 22:12:10 +0200 Date: Thu, 02 Jun 2011 20:12:00 -0000 From: Jan Kratochvil To: Tom Tromey Cc: gdb-patches@sourceware.org Subject: Re: [patch] Follow DW_AT_linkage_name for methods #2 Message-ID: <20110602201210.GA31484@host1.jankratochvil.net> References: <20110602190245.GC28038@host1.jankratochvil.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-IsSubscribed: yes Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2011-06/txt/msg00040.txt.bz2 On Thu, 02 Jun 2011 22:08:02 +0200, Tom Tromey wrote: > >>>>> "Jan" == Jan Kratochvil writes: > > Jan> this is a repost of already approved: > Jan> [rfc 2/2] Follow DW_AT_linkage_name for methods [Re: The future of dwarf2_physname] > Jan> http://sourceware.org/ml/gdb-patches/2011-05/msg00579.html > Jan> http://sourceware.org/ml/gdb-patches/2011-06/msg00012.html > > I think the doc patch should be part of this as well. Sorry, yes, you have sent it to me off-list. Thanks, Jan gdb/ 2011-05-24 Jan Kratochvil Tom Tromey * dwarf2read.c (check_physname): New variable. (dwarf2_physname): Prefer DW_AT_linkage_name over dwarf2_compute_name. (show_check_physname): New function. (_initialize_dwarf2_read): Add `check-physname' for check_physname. gdb/doc/ 2011-05-26 Tom Tromey * gdb.texinfo (Debugging Output): Document set debug check-physname. gdb/testsuite/ 2011-05-24 Jan Kratochvil * gdb.base/break-interp.exp (reach_1, test_ld): Allow also the prefix __GI_. * gdb.cp/psymtab-parameter.cc (func): Make it a template function. (f): New function. * gdb.cp/psymtab-parameter.exp (complete break 'func(): Rename to ... (complete p 'func(): ... here. * gdb.dwarf2/dw2-linkage-name-trust-main.cc: New file. * gdb.dwarf2/dw2-linkage-name-trust.S: New file. * gdb.dwarf2/dw2-linkage-name-trust.exp: New file. --- a/gdb/doc/gdb.texinfo +++ b/gdb/doc/gdb.texinfo @@ -20027,6 +20027,16 @@ Display debugging messages about inner workings of the AIX thread module. @item show debug aix-thread Show the current state of AIX thread debugging info display. +@item set debug check-physname +@cindex physname +Check the results of the ``physname'' computation. When reading DWARF +debugging information for C@t{++}, @value{GDBN} attempts to compute +each entity's name. @value{GDBN} can do this computation in two +different ways, depending on exactly what information is present. +When enabled, this setting causes @value{GDBN} to compute the names +both ways and display any discrepancies. +@item show debug check-physname +Show the current state of ``physname'' checking. @item set debug dwarf2-die @cindex DWARF2 DIEs Dump DWARF2 DIEs after they are read in. --- a/gdb/dwarf2read.c +++ b/gdb/dwarf2read.c @@ -119,6 +119,9 @@ _STATEMENT_PROLOGUE; /* When non-zero, dump DIEs after they are read in. */ static int dwarf2_die_debug = 0; +/* When non-zero, cross-check physname against demangler. */ +static int check_physname = 0; + static int pagesize; /* When set, the file that we're processing is known to have debugging @@ -5170,7 +5173,92 @@ dwarf2_full_name (char *name, struct die_info *die, struct dwarf2_cu *cu) static const char * dwarf2_physname (char *name, struct die_info *die, struct dwarf2_cu *cu) { - return dwarf2_compute_name (name, die, cu, 1); + struct attribute *attr; + const char *retval, *mangled = NULL, *canon = NULL; + struct cleanup *back_to; + int need_copy = 1; + + /* In this case dwarf2_compute_name is just a shortcut not building anything + on its own. */ + if (!die_needs_namespace (die, cu)) + return dwarf2_compute_name (name, die, cu, 1); + + back_to = make_cleanup (null_cleanup, NULL); + + attr = dwarf2_attr (die, DW_AT_linkage_name, cu); + if (!attr) + attr = dwarf2_attr (die, DW_AT_MIPS_linkage_name, cu); + + /* DW_AT_linkage_name is missing in some cases - depend on what GDB + has computed. */ + if (attr && DW_STRING (attr)) + { + char *demangled; + + mangled = DW_STRING (attr); + + /* Use DMGL_RET_DROP for C++ template functions to suppress their return + type. It is easier for GDB users to search for such functions as + `name(params)' than `long name(params)'. In such case the minimal + symbol names do not match the full symbol names but for template + functions there is never a need to look up their definition from their + declaration so the only disadvantage remains the minimal symbol + variant `long name(params)' does not have the proper inferior type. + */ + + demangled = cplus_demangle (mangled, (DMGL_PARAMS | DMGL_ANSI + | DMGL_VERBOSE + | (cu->language == language_java + ? DMGL_JAVA | DMGL_RET_POSTFIX + : DMGL_RET_DROP))); + if (demangled) + { + make_cleanup (xfree, demangled); + canon = demangled; + } + else + { + canon = mangled; + need_copy = 0; + } + } + + if (canon == NULL || check_physname) + { + const char *physname = dwarf2_compute_name (name, die, cu, 1); + + if (canon != NULL && strcmp (physname, canon) != 0) + { + /* It may not mean a bug in GDB. The compiler could also + compute DW_AT_linkage_name incorrectly. But in such case + GDB would need to be bug-to-bug compatible. */ + + complaint (&symfile_complaints, + _("Computed physname <%s> does not match demangled <%s> " + "(from linkage <%s>) - DIE at 0x%x [in module %s]"), + physname, canon, mangled, die->offset, cu->objfile->name); + + /* Prefer DW_AT_linkage_name (in the CANON form) - when it + is available here - over computed PHYSNAME. It is safer + against both buggy GDB and buggy compilers. */ + + retval = canon; + } + else + { + retval = physname; + need_copy = 0; + } + } + else + retval = canon; + + if (need_copy) + retval = obsavestring (retval, strlen (retval), + &cu->objfile->objfile_obstack); + + do_cleanups (back_to); + return retval; } /* Read the import statement specified by the given die and record it. */ @@ -16188,6 +16276,15 @@ show_dwarf2_always_disassemble (struct ui_file *file, int from_tty, value); } +static void +show_check_physname (struct ui_file *file, int from_tty, + struct cmd_list_element *c, const char *value) +{ + fprintf_filtered (file, + _("Whether to check \"physname\" is %s.\n"), + value); +} + void _initialize_dwarf2_read (void); void @@ -16243,6 +16340,14 @@ The value is the maximum depth to print."), NULL, &setdebuglist, &showdebuglist); + add_setshow_boolean_cmd ("check-physname", no_class, &check_physname, _("\ +Set cross-checking of \"physname\" code against demangler."), _("\ +Show cross-checking of \"physname\" code against demangler."), _("\ +When enabled, GDB's internal \"physname\" code is checked against\n\ +the demangler."), + NULL, show_check_physname, + &setdebuglist, &showdebuglist); + c = add_cmd ("gdb-index", class_files, save_gdb_index_command, _("\ Save a gdb-index file.\n\ --- a/gdb/testsuite/gdb.base/break-interp.exp +++ b/gdb/testsuite/gdb.base/break-interp.exp @@ -140,14 +140,14 @@ proc reach_1 {func command displacement} { } exp_continue } - -re "Breakpoint \[0-9\]+, \\.?$func \\(.*\\) at .*:\[0-9\]+\r\n.*$gdb_prompt $" { + -re "Breakpoint \[0-9\]+, \\.?(__GI_)?$func \\(.*\\) at .*:\[0-9\]+\r\n.*$gdb_prompt $" { if {$func == "_dl_debug_state"} { fail $test } else { pass $test } } - -re "Breakpoint \[0-9\]+, \[0-9xa-f\]+ in \\.?$func \\(\\).*\r\n$gdb_prompt $" { + -re "Breakpoint \[0-9\]+, \[0-9xa-f\]+ in \\.?(__GI_)?$func \\(\\).*\r\n$gdb_prompt $" { if {$func == "_dl_debug_state"} { fail $test } else { @@ -403,7 +403,7 @@ proc test_ld {file ifmain trynosym displacement} { reach "_dl_debug_state" "run" $displacement - gdb_test "bt" "#0 +\[^\r\n\]*\\m_dl_debug_state\\M.*" "dl bt" + gdb_test "bt" "#0 +\[^\r\n\]*\\m(__GI_)?_dl_debug_state\\M.*" "dl bt" if $ifmain { reach "main" continue "NONE" --- a/gdb/testsuite/gdb.cp/psymtab-parameter.cc +++ b/gdb/testsuite/gdb.cp/psymtab-parameter.cc @@ -16,7 +16,14 @@ along with this program. If not, see . */ -typedef int typedefed; -void func (typedefed param) +template +long +func () { } + +void +f () +{ + func (); +} --- a/gdb/testsuite/gdb.cp/psymtab-parameter.exp +++ b/gdb/testsuite/gdb.cp/psymtab-parameter.exp @@ -35,5 +35,6 @@ gdb_test_no_output "set language c++" # XFAIL than FAIL here. For example -readnow breaks it. gdb_test_no_output "maintenance info symtabs" -# GDB has shown only the `func(int)' entry before. -gdb_test "complete break 'func(" "break 'func\\(int\\)\r\nbreak 'func\\(typedefed\\)" +# GDB has shown only the `long func()' ELF symbol before, not the DWARF +# symbol +gdb_test "complete p 'func(" "p 'func\\(\\)" --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/dw2-linkage-name-trust-main.cc @@ -0,0 +1,41 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2011 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 . */ + +/* class C + { + public: + static int f (); + }; */ + +asm (".globl cu_text_start"); +asm ("cu_text_start:"); + +int +f (void) +{ + return 31173; +} + +int +main (void) +{ + f (); + return 0; +} + +asm (".globl cu_text_end"); +asm ("cu_text_end:"); --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/dw2-linkage-name-trust.S @@ -0,0 +1,134 @@ +/* This testcase is part of GDB, the GNU debugger. + + Copyright 2011 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 . */ + +/* Debug information */ + + .data + .globl c +c: .4byte 0 + + .section .debug_info +.Lcu1_begin: + /* CU header */ + .4byte .Lcu1_end - .Lcu1_start /* Length of Compilation Unit */ +.Lcu1_start: + .2byte 2 /* DWARF Version */ + .4byte .Labbrev1_begin /* Offset into abbrev section */ + .byte 4 /* Pointer size */ + + /* CU die */ + .uleb128 1 /* Abbrev: DW_TAG_compile_unit */ + .4byte cu_text_start /* DW_AT_low_pc */ + .4byte cu_text_end /* DW_AT_high_pc */ + .ascii "file1.txt\0" /* DW_AT_name */ + .ascii "GNU C 3.3.3\0" /* DW_AT_producer */ + .byte 4 /* DW_AT_language (DW_LANG_C_plus_plus) */ + +.Ltype_class: + .uleb128 3 /* Abbrev: DW_TAG_class_type */ + .ascii "C\0" /* DW_AT_name */ + + .uleb128 5 /* Abbrev: DW_TAG_subprogram */ + .byte 1 /* DW_AT_external */ + .ascii "membername\0" /* DW_AT_name */ + .ascii "f\0" /* DW_AT_MIPS_linkage_name */ + .4byte .Ltype_int-.Lcu1_begin /* DW_AT_type */ + + .byte 0 /* End of children of DW_TAG_class_type */ + + .uleb128 4 /* Abbrev: DW_TAG_variable */ + .ascii "c\0" /* DW_AT_name */ + .4byte .Ltype_class-.Lcu1_begin /* DW_AT_type */ + .byte 1 /* DW_AT_external */ + +.Ltype_int: + .uleb128 2 /* Abbrev: DW_TAG_base_type */ + .ascii "int\0" /* DW_AT_name */ + .byte 4 /* DW_AT_byte_size */ + .byte 5 /* DW_AT_encoding */ + + .byte 0 /* End of children of CU */ + +.Lcu1_end: + +/* Abbrev table */ + .section .debug_abbrev +.Labbrev1_begin: + .uleb128 1 /* Abbrev code */ + .uleb128 0x11 /* DW_TAG_compile_unit */ + .byte 1 /* has_children */ + .uleb128 0x11 /* DW_AT_low_pc */ + .uleb128 0x1 /* DW_FORM_addr */ + .uleb128 0x12 /* DW_AT_high_pc */ + .uleb128 0x1 /* DW_FORM_addr */ + .uleb128 0x3 /* DW_AT_name */ + .uleb128 0x8 /* DW_FORM_string */ + .uleb128 0x25 /* DW_AT_producer */ + .uleb128 0x8 /* DW_FORM_string */ + .uleb128 0x13 /* DW_AT_language */ + .uleb128 0xb /* DW_FORM_data1 */ + .byte 0x0 /* Terminator */ + .byte 0x0 /* Terminator */ + + .uleb128 2 /* Abbrev code */ + .uleb128 0x24 /* DW_TAG_base_type */ + .byte 0 /* has_children */ + .uleb128 0x3 /* DW_AT_name */ + .uleb128 0x8 /* DW_FORM_string */ + .uleb128 0xb /* DW_AT_byte_size */ + .uleb128 0xb /* DW_FORM_data1 */ + .uleb128 0x3e /* DW_AT_encoding */ + .uleb128 0xb /* DW_FORM_data1 */ + .byte 0x0 /* Terminator */ + .byte 0x0 /* Terminator */ + + .uleb128 3 /* Abbrev code */ + .uleb128 0x2 /* DW_TAG_class_type */ + .byte 1 /* has_children */ + .uleb128 0x3 /* DW_AT_name */ + .uleb128 0x8 /* DW_FORM_string */ + .byte 0x0 /* Terminator */ + .byte 0x0 /* Terminator */ + + .uleb128 4 /* Abbrev code */ + .uleb128 0x34 /* DW_TAG_variable */ + .byte 0 /* has_children */ + .uleb128 0x3 /* DW_AT_name */ + .uleb128 0x8 /* DW_FORM_string */ + .uleb128 0x49 /* DW_AT_type */ + .uleb128 0x13 /* DW_FORM_ref4 */ + .uleb128 0x3f /* DW_AT_external */ + .uleb128 0xc /* DW_FORM_flag */ + .byte 0x0 /* Terminator */ + .byte 0x0 /* Terminator */ + + .uleb128 5 /* Abbrev code */ + .uleb128 0x2e /* DW_TAG_subprogram */ + .byte 0 /* has_children */ + .uleb128 0x3f /* DW_AT_external */ + .uleb128 0xc /* DW_FORM_flag */ + .uleb128 0x3 /* DW_AT_name */ + .uleb128 0x8 /* DW_FORM_string */ + .uleb128 0x2007 /* DW_AT_MIPS_linkage_name */ + .uleb128 0x8 /* DW_FORM_string */ + .uleb128 0x49 /* DW_AT_type */ + .uleb128 0x13 /* DW_FORM_ref4 */ + .byte 0x0 /* Terminator */ + .byte 0x0 /* Terminator */ + + .byte 0x0 /* Terminator */ + .byte 0x0 /* Terminator */ --- /dev/null +++ b/gdb/testsuite/gdb.dwarf2/dw2-linkage-name-trust.exp @@ -0,0 +1,55 @@ +# Copyright 2011 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 . + +# Check that GDB can call C++ functions whose parameters or return values have +# type containing a static member of the same type. + +# Still no C++ compiler is used. +if { [skip_cplus_tests] } { continue } + +load_lib dwarf.exp +# This test can only be run on targets which support DWARF-2 and use gas. +if {![dwarf2_support]} { + return 0 +} + +set testfile "dw2-linkage-name-trust" +set executable ${testfile} +set binfile ${objdir}/${subdir}/${executable} +if { [gdb_compile ${srcdir}/${subdir}/${testfile}-main.cc "${objdir}/${subdir}/${testfile}-main.o" object {c++ debug}] != "" + || [gdb_compile "${srcdir}/${subdir}/${testfile}.S" "${objdir}/${subdir}/${testfile}.o" object {}] != "" + || [gdb_compile "${objdir}/${subdir}/${testfile}-main.o ${objdir}/${subdir}/${testfile}.o" "${binfile}" executable {c++}] != "" } { + return -1 +} + +clean_restart $executable + +if ![runto_main] then { + return -1 +} + +# main is not provided by DWARF. +gdb_test_no_output "set language c++" + +# There are no mangled names in DWARF to suggest the v3 ABI. +gdb_test_no_output "set cp-abi gnu-v3" + +# GDB cannot resolve external member function for which only ELF (and not +# DWARF) symbol is available. Therefore the function `f' must have DWARF which +# confuses it a bit. + +gdb_test "p c.membername" " = {.*} 0x\[0-9a-f\]+ " +gdb_breakpoint "C::membername" +gdb_test "p c.membername ()" "\r\nBreakpoint \[0-9\]+, .*"