2006-10-30 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb/minsyms.c (lookup_minimal_symbol_by_pc_section): Handle
overlapping non-zero sized functions (for glibc `__nanosleep').
2006-10-30 Jan Kratochvil <jan.kratochvil@redhat.com>
* gdb.arch/i386-size-overlap.c, gdb.arch/i386-size-overlap.exp: New
file, provide nested (overlapping) functions for the PC resolving.
--- gdb-6.5/gdb/minsyms.c-orig 2006-10-31 08:21:32.000000000 -0500
+++ gdb-6.5/gdb/minsyms.c 2006-10-31 08:24:37.000000000 -0500
@@ -464,6 +464,7 @@
objfile's minimal symbol table. See if it is the best one
overall. */
+ while (0
/* Skip any absolute symbols. This is apparently what adb
and dbx do, and is needed for the CM-5. There are two
known possible problems: (1) on ELF, apparently end, edata,
@@ -473,8 +474,27 @@
NeXT are absolute. If we want special handling for this
it probably should be triggered by a special
mst_abs_or_lib or some such. */
- while (hi >= 0
- && msymbol[hi].type == mst_abs)
+ || (hi >= 0
+ && msymbol[hi].type == mst_abs)
+ /* We are behind the current symbol's size.
+ Try the previous symbol - if it is non-zero sized one it
+ may overlap the current one and reach our PC.
+ It occurs for GNU/Linux glibc `__nanosleep' overlapping
+ later `__nanosleep_nocancel' with PC at 0077ec66:
+ Num: Value Size Type Bind Vis Ndx Name
+ 7247: 0077ec20 124 FUNC WEAK DEFAULT 11 __nanosleep
+ 4651: 0077ec2a 32 FUNC LOCAL DEFAULT 11 __nanosleep_nocancel
+ Test `gdb.arch/i386-size' + `gdb.arch/i386-unwind'.
+ Limit it only for the overlapping cases as we could harm
+ the zero-sized symbols detection logic around.
+ */
+ || (hi > 0
+ && MSYMBOL_SIZE (&msymbol[hi]) != 0
+ && pc >= (SYMBOL_VALUE_ADDRESS (&msymbol[hi])
+ + MSYMBOL_SIZE (&msymbol[hi]))
+ && pc < (SYMBOL_VALUE_ADDRESS (&msymbol[hi - 1])
+ + MSYMBOL_SIZE (&msymbol[hi - 1])))
+ )
--hi;
/* If "section" specified, skip any symbol from wrong section */
Index: ./gdb/testsuite/gdb.arch/i386-size-overlap.c
===================================================================
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ ./gdb/testsuite/gdb.arch/i386-size-overlap.c 30 Oct 2006 12:41:35 -0000
@@ -0,0 +1,53 @@
+/* Overlapping symbol sizes test program.
+
+ Copyright 2006 Free Software Foundation, Inc.
+
+ This file is part of GDB.
+
+ 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 2 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, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330,
+ Boston, MA 02111-1307, USA. */
+
+#ifdef SYMBOL_PREFIX
+#define SYMBOL(str) SYMBOL_PREFIX #str
+#else
+#define SYMBOL(str) #str
+#endif
+
+void
+trap (void)
+{
+ asm ("int $0x03");
+}
+
+/* Jump from a function with its symbol size set, to a function
+ named by a local label. GDB should report the `main' function
+ even for the rest, after the global `inner' ends. */
+
+asm(".text\n"
+ " .align 8\n"
+ " .globl " SYMBOL (main) "\n"
+ SYMBOL (main) ":\n"
+ " pushl %ebp\n"
+ " mov %esp, %ebp\n"
+ " call .Lfunc\n"
+ " ret\n"
+ SYMBOL (inner) ":\n"
+ " ret\n"
+ " .size " SYMBOL (inner) ", .-" SYMBOL (inner) "\n"
+ ".Lfunc:\n"
+ " pushl %ebp\n"
+ " mov %esp, %ebp\n"
+ " call " SYMBOL (trap) "\n"
+ " .size " SYMBOL (main) ", .-" SYMBOL (main) "\n");
Index: ./gdb/testsuite/gdb.arch/i386-size-overlap.exp
===================================================================
RCS file: gdb/testsuite/gdb.arch/i386-size-overlap.exp
diff -N gdb/testsuite/gdb.arch/i386-size-overlap.exp
--- /dev/null 1 Jan 1970 00:00:00 -0000
+++ ./gdb/testsuite/gdb.arch/i386-size-overlap.exp 30 Oct 2006 12:41:35 -0000
@@ -0,0 +1,79 @@
+# Copyright 2006 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 2 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, write to the Free Software
+# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+# Please email any bugs, comments, and/or additions to this file to:
+# bug-gdb@gnu.org
+
+# This file is part of the gdb testsuite.
+
+if $tracelevel {
+ strace $tracelevel
+}
+
+# Test that GDB can handle overlapping sizes of symbols.
+
+if ![istarget "i?86-*-*"] then {
+ verbose "Skipping i386 unwinder tests."
+ return
+}
+
+set testfile "i386-size-overlap"
+set srcfile ${testfile}.c
+set binfile ${objdir}/${subdir}/${testfile}
+
+# some targets have leading underscores on assembly symbols.
+# TODO: detect this automatically
+set additional_flags ""
+if [istarget "i?86-*-cygwin*"] then {
+ set additional_flags "additional_flags=-DSYMBOL_PREFIX=\"_\""
+}
+
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" \
+ executable [list debug $additional_flags]] != "" } {
+ untested "i386-size"
+ return -1
+}
+
+gdb_exit
+gdb_start
+gdb_reinitialize_dir $srcdir/$subdir
+gdb_load ${binfile}
+
+# We use gdb_run_cmd so this stands a chance to work for remote
+# targets too.
+gdb_run_cmd
+
+gdb_expect {
+ -re "Program received signal SIGTRAP.*$gdb_prompt $" {
+ pass "run past main"
+ }
+ -re ".*$gdb_prompt $" {
+ fail "run past main"
+ }
+ timeout {
+ fail "run past main (timeout)"
+ }
+}
+
+set message "backtrace shows the outer function"
+gdb_test_multiple "backtrace 10" $message {
+ -re "#1\[ \t]*$hex in inner.*$gdb_prompt $" {
+ fail $message
+ }
+ -re "#1\[ \t]*$hex in main.*$gdb_prompt $" {
+ pass $message
+ }
+}