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.

Index: ./gdb/minsyms.c

===================================================================

--- ./gdb/minsyms.c	17 Oct 2006 20:17:44 -0000	1.47

+++ ./gdb/minsyms.c	30 Oct 2006 12:41:26 -0000

@@ -511,6 +511,29 @@ lookup_minimal_symbol_by_pc_section (COR

 		      continue;

 		    }

+		  /* 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.

+		     */

+		  if (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--;

+		      continue;

+		    }

+

 		  /* Otherwise, this symbol must be as good as we're going

 		     to get.  */

 		  break;

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

+    }

+}