From af312be73153278ccc14e39c40a2bb0923578aa8 Mon Sep 17 00:00:00 2001 From: Joel Brobecker Date: Fri, 29 Mar 2013 02:04:15 +0000 Subject: [PATCH] Ignore __fu__ symbols from COFF symbol tables The debugger sometimes prints strange function names for given addresses. For instance, with the following source code... 4 procedure Foo is 5 A : Integer; 6 begin 7 Do_Nothing (A'Address); 8 end Foo; ... we can see... (gdb) info line 5 Line 5 of "foo.adb" starts at address 0x4017ca <_ada_foo+6> and ends at 0x4017d2 <_fu29__system__scalar_values__is_is4+7>. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ _fu29__system__scalar_values__is_is4 is an artificial symbol generated by the linker, and interferes with the pc-to-symbol resolution. There isn't much in the general minimal_symbol data that could help us identify them, so this patch changes the COFF reader to simply ignore them. gdb/ChangeLog: * coffread.c (is_import_fixup_symbol): New function. (record_minimal_symbol): Use is_import_fixup_symbol to detect import fixup symbols, and discard them. gdb/testsuite/ChangeLog: * gdb.ada/win_fu_syms: New testcase. --- gdb/ChangeLog | 6 +++++ gdb/coffread.c | 43 +++++++++++++++++++++++++++++++ gdb/testsuite/ChangeLog | 4 +++ gdb/testsuite/gdb.ada/win_fu_syms.exp | 35 +++++++++++++++++++++++++ gdb/testsuite/gdb.ada/win_fu_syms/foo.adb | 23 +++++++++++++++++ gdb/testsuite/gdb.ada/win_fu_syms/pck.adb | 21 +++++++++++++++ gdb/testsuite/gdb.ada/win_fu_syms/pck.ads | 19 ++++++++++++++ 7 files changed, 151 insertions(+) create mode 100644 gdb/testsuite/gdb.ada/win_fu_syms.exp create mode 100644 gdb/testsuite/gdb.ada/win_fu_syms/foo.adb create mode 100644 gdb/testsuite/gdb.ada/win_fu_syms/pck.adb create mode 100644 gdb/testsuite/gdb.ada/win_fu_syms/pck.ads diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 9dbcc16..3b7926a 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,9 @@ +2013-03-28 Joel Brobecker + + * coffread.c (is_import_fixup_symbol): New function. + (record_minimal_symbol): Use is_import_fixup_symbol to + detect import fixup symbols, and discard them. + 2013-03-28 Doug Evans * dwarf2read.c (create_debug_types_hash_table): Don't allocate the diff --git a/gdb/coffread.c b/gdb/coffread.c index c390880..eff8d64 100644 --- a/gdb/coffread.c +++ b/gdb/coffread.c @@ -418,6 +418,39 @@ coff_end_symtab (struct objfile *objfile) set_last_source_file (NULL); } +/* The linker sometimes generates some non-function symbols inside + functions referencing variables imported from another DLL. + Return nonzero if the given symbol corresponds to one of them. */ + +static int +is_import_fixup_symbol (struct coff_symbol *cs, + enum minimal_symbol_type type) +{ + /* The following is a bit of a heuristic using the characterictics + of these fixup symbols, but should work well in practice... */ + int i; + + /* Must be a non-static text symbol. */ + if (type != mst_text) + return 0; + + /* Must be a non-function symbol. */ + if (ISFCN (cs->c_type)) + return 0; + + /* The name must start with "__fu__". */ + if (strncmp (cs->c_name, "__fu", 4) != 0) + return 0; + if (! isdigit (cs->c_name[4])) + return 0; + for (i = 5; cs->c_name[i] != '\0' && isdigit (cs->c_name[i]); i++) + /* Nothing, just incrementing index past all digits. */; + if (cs->c_name[i] != '_' || cs->c_name[i + 1] != '_') + return 0; + + return 1; +} + static struct minimal_symbol * record_minimal_symbol (struct coff_symbol *cs, CORE_ADDR address, enum minimal_symbol_type type, int section, @@ -429,6 +462,16 @@ record_minimal_symbol (struct coff_symbol *cs, CORE_ADDR address, if (cs->c_name[0] == '@') return NULL; + if (is_import_fixup_symbol (cs, type)) + { + /* Because the value of these symbols is within a function code + range, these symbols interfere with the symbol-from-address + reverse lookup; this manifests itselfs in backtraces, or any + other commands that prints symbolic addresses. Just pretend + these symbols do not exist. */ + return NULL; + } + bfd_section = cs_to_bfd_section (cs, objfile); return prim_record_minimal_symbol_and_info (cs->c_name, address, type, section, diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog index f153116..9c835f2 100644 --- a/gdb/testsuite/ChangeLog +++ b/gdb/testsuite/ChangeLog @@ -1,3 +1,7 @@ +2013-03-28 Joel Brobecker + + * gdb.ada/win_fu_syms: New testcase. + 2013-03-28 Doug Evans * gdb.base/maint.exp (maint print statistics): Update expected output. diff --git a/gdb/testsuite/gdb.ada/win_fu_syms.exp b/gdb/testsuite/gdb.ada/win_fu_syms.exp new file mode 100644 index 0000000..c3cbf16 --- /dev/null +++ b/gdb/testsuite/gdb.ada/win_fu_syms.exp @@ -0,0 +1,35 @@ +# 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 . + +load_lib "ada.exp" + +standard_ada_testfile foo + +if {[gdb_compile_ada "${srcfile}" "${binfile}" executable [list debug additional_flags=-bargs additional_flags=-shared additional_flags=-margs]] != "" } { + return -1 +} + +clean_restart ${testfile} + +set loc [gdb_get_line_number "Integer" ${testdir}/foo.adb] +gdb_test "info line foo.adb:$loc" \ + "Line $decimal of \".*foo\\.adb\" starts at address $hex <_ada_foo\\+$decimal> and ends at $hex <_ada_foo\\+$decimal>\\." \ + "info line on variable declaration" + +set loc [gdb_get_line_number "Do_Nothing" ${testdir}/foo.adb] +gdb_test "info line foo.adb:$loc" \ + "Line $decimal of \".*foo\\.adb\" starts at address $hex <_ada_foo\\+$decimal> and ends at $hex <_ada_foo\\+$decimal>\\." \ + "info line on Do_Nothing call" + diff --git a/gdb/testsuite/gdb.ada/win_fu_syms/foo.adb b/gdb/testsuite/gdb.ada/win_fu_syms/foo.adb new file mode 100644 index 0000000..a09a346 --- /dev/null +++ b/gdb/testsuite/gdb.ada/win_fu_syms/foo.adb @@ -0,0 +1,23 @@ +-- 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 . + +pragma Initialize_Scalars; +with Pck; use Pck; + +procedure Foo is + A : Integer; +begin + Do_Nothing (A'Address); +end Foo; diff --git a/gdb/testsuite/gdb.ada/win_fu_syms/pck.adb b/gdb/testsuite/gdb.ada/win_fu_syms/pck.adb new file mode 100644 index 0000000..808da4db --- /dev/null +++ b/gdb/testsuite/gdb.ada/win_fu_syms/pck.adb @@ -0,0 +1,21 @@ +-- Copyright 2007-2013 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 . + +package body Pck is + procedure Do_Nothing (A : System.Address) is + begin + null; + end Do_Nothing; +end Pck; diff --git a/gdb/testsuite/gdb.ada/win_fu_syms/pck.ads b/gdb/testsuite/gdb.ada/win_fu_syms/pck.ads new file mode 100644 index 0000000..d5791b2 --- /dev/null +++ b/gdb/testsuite/gdb.ada/win_fu_syms/pck.ads @@ -0,0 +1,19 @@ +-- Copyright 2007-2013 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 . + +with System; +package Pck is + procedure Do_Nothing (A : System.Address); +end Pck; -- 2.7.4