From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 2135 invoked by alias); 15 Feb 2005 21:17:11 -0000 Mailing-List: contact gdb-patches-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sources.redhat.com Received: (qmail 1902 invoked from network); 15 Feb 2005 21:16:59 -0000 Received: from unknown (HELO e31.co.us.ibm.com) (32.97.110.129) by sourceware.org with SMTP; 15 Feb 2005 21:16:59 -0000 Received: from westrelay02.boulder.ibm.com (westrelay02.boulder.ibm.com [9.17.195.11]) by e31.co.us.ibm.com (8.12.10/8.12.9) with ESMTP id j1FLGwua518494 for ; Tue, 15 Feb 2005 16:16:58 -0500 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by westrelay02.boulder.ibm.com (8.12.10/NCO/VER6.6) with ESMTP id j1FLGwp8453264 for ; Tue, 15 Feb 2005 14:16:58 -0700 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.12.11/8.12.11) with ESMTP id j1FLGw4Q013800 for ; Tue, 15 Feb 2005 14:16:58 -0700 Received: from austin.ibm.com (netmail2.austin.ibm.com [9.41.248.176]) by d03av02.boulder.ibm.com (8.12.11/8.12.11) with ESMTP id j1FLGwJK013772 for ; Tue, 15 Feb 2005 14:16:58 -0700 Received: from lazy.austin.ibm.com (lazy.austin.ibm.com [9.53.94.97]) by austin.ibm.com (8.12.10/8.12.10) with ESMTP id j1FLGsOV046580 for ; Tue, 15 Feb 2005 15:16:55 -0600 Date: Wed, 16 Feb 2005 00:17:00 -0000 From: Manoj Iyer X-X-Sender: manjo@lazy To: gdb-patches@sources.redhat.com Subject: [RFC] Dont skip DW_TAG_member in load_partial_dies() Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-SW-Source: 2005-02/txt/msg00155.txt.bz2 GDB prints internal error with C++ application produced by XLC. =============== Test Case ======================== /* This testcase written by Lu Yang */ template class X; template class Y { friend class X; public: T f(); }; template class X { public: friend inline T Y::f(); static T a; }; template inline T Y::f() {return X::a;} template<> int X::a =5; int main() { Y obj; if (obj.f() == 5) return 55; else return 66; } ====================== End Test Case ===================== When the above testcase is compiled -m64 by XLC, GDB generates an internal error: "internal-error: could not find partial DIE in cache" GCC creates a DWARF TAG for "a" as DW_TAG_variable and XLC creates DW_TAG_member. GDB throws away TAGS that it find as uninteresting. In this case DW_TAG_member. (this is in dwarf2read.c function: load_partial_dies(). ) GCC created DWARF information ------------------------------- <2><102>: Abbrev Number: 13 (DW_TAG_variable) DW_AT_name : a DW_AT_decl_file : 1 DW_AT_decl_line : 13 DW_AT_MIPS_linkage_name: _ZN1XIiE1aE DW_AT_type : DW_AT_external : 1 DW_AT_declaration : 1 XLC created DWARF information ------------------------------ <2><96>: Abbrev Number: 5 (DW_TAG_member) DW_AT_name : a DW_AT_accessibility: 1 (public) DW_AT_declaration : 1 DW_AT_type : <78> GCC in this case is producing wrong information. According to DWARF spec: " If the variable entry represents the defining declaration for a C++ static data member of a structure, class or union, the entry has a DW_AT_specification attribute, whose value is a reference to the debugging information entry representing the declaration of this data member. The referenced entry has the tag DW_TAG_member and will be a child of some class, structure or union type entry. " So I think GDB needs to handle the DW_TAG_member and not skip it, when dealing with C++. Here is a patch to GDB that will fix this problem ================ Patch to gdb ================== 2005-02-15 Manoj Iyer * dwarf2read.c (load_partial_dies): Save DIE with tag DW_TAG_member, generated by XLC when compiling C++ application. diff -Naur ./old/src/gdb/dwarf2read.c ./new/src/gdb/dwarf2read.c --- ./old/src/gdb/dwarf2read.c 2005-02-15 11:13:05.000000000 -0600 +++ ./new/src/gdb/dwarf2read.c 2005-02-22 10:24:08.000000000 -0600 @@ -5167,7 +5167,8 @@ && abbrev->tag != DW_TAG_enumerator && abbrev->tag != DW_TAG_subprogram && abbrev->tag != DW_TAG_variable - && abbrev->tag != DW_TAG_namespace) + && abbrev->tag != DW_TAG_namespace + && abbrev->tag != DW_TAG_member) { /* Otherwise we skip to the next sibling, if any. */ info_ptr = skip_one_die (info_ptr + bytes_read, abbrev, cu); ========================= END PATCH ====================== ok to commit? Thanks ----- manjo +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ + Cogito ergo sum + +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++