gdb/

* dwarf2read.c (dwarf2_get_pc_bounds): Require HIGH strictly higher
	than LOW.  Comment it.
	(read_partial_die): Call complaint for inappropriate zero LOWPC or
	HIGHPC not strictly higher than LOWPC.

gdb/testsuite/
	* gdb.dwarf2/dw2-empty-pc-range.S: New file.
	* gdb.dwarf2/dw2-empty-pc-range.exp: New file.
	* gdb.dwarf2/pr11465.S: New .text labels text_start and text_end.
	Provide a stub byte there.
	(DW_TAG_compile_unit): Set DW_AT_low_pc, DW_AT_high_pc and
	DW_AT_entry_pc.
	(dieb4, dieda): Set DW_AT_high_pc higher than DW_AT_low_pc.

gdb/ChangeLog

@@ -1,3 +1,10 @@
+2011-03-15  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+	* dwarf2read.c (dwarf2_get_pc_bounds): Require HIGH strictly higher
+	than LOW.  Comment it.
+	(read_partial_die): Call complaint for inappropriate zero LOWPC or
+	HIGHPC not strictly higher than LOWPC.
+
 2011-03-15  Pierre Muller  <muller@ics.u-strasbg.fr>
 
 	Fix formatting of function declarations returning a pointer in

gdb/dwarf2read.c

@@ -5982,7 +5982,8 @@ dwarf2_get_pc_bounds (struct die_info *die, CORE_ADDR *lowpc,
 	}
     }
 
-  if (high < low)
+  /* read_partial_die has also the strict LOW < HIGH requirement.  */
+  if (high <= low)
     return 0;
 
   /* When using the GNU linker, .gnu.linkonce. sections are used to
@@ -9127,19 +9128,41 @@ read_partial_die (struct partial_die_info *part_die,
 	}
     }
 
-  /* When using the GNU linker, .gnu.linkonce. sections are used to
-     eliminate duplicate copies of functions and vtables and such.
-     The linker will arbitrarily choose one and discard the others.
-     The AT_*_pc values for such functions refer to local labels in
-     these sections.  If the section from that file was discarded, the
-     labels are not in the output, so the relocs get a value of 0.
-     If this is a discarded function, mark the pc bounds as invalid,
-     so that GDB will ignore it.  */
-  if (has_low_pc_attr && has_high_pc_attr
-      && part_die->lowpc < part_die->highpc
-      && (part_die->lowpc != 0
-	  || dwarf2_per_objfile->has_section_at_zero))
-    part_die->has_pc_info = 1;
+  if (has_low_pc_attr && has_high_pc_attr)
+    {
+      /* When using the GNU linker, .gnu.linkonce. sections are used to
+	 eliminate duplicate copies of functions and vtables and such.
+	 The linker will arbitrarily choose one and discard the others.
+	 The AT_*_pc values for such functions refer to local labels in
+	 these sections.  If the section from that file was discarded, the
+	 labels are not in the output, so the relocs get a value of 0.
+	 If this is a discarded function, mark the pc bounds as invalid,
+	 so that GDB will ignore it.  */
+      if (part_die->lowpc == 0 && !dwarf2_per_objfile->has_section_at_zero)
+	{
+	  struct gdbarch *gdbarch = get_objfile_arch (cu->objfile);
+
+	  complaint (&symfile_complaints,
+		     _("DW_AT_low_pc %s is zero "
+		       "for DIE at 0x%x [in module %s]"),
+		     paddress (gdbarch, part_die->lowpc),
+		     part_die->offset, cu->objfile->name);
+	}
+      /* dwarf2_get_pc_bounds has also the strict low < high requirement.  */
+      else if (part_die->lowpc >= part_die->highpc)
+	{
+	  struct gdbarch *gdbarch = get_objfile_arch (cu->objfile);
+
+	  complaint (&symfile_complaints,
+		     _("DW_AT_low_pc %s is not < DW_AT_high_pc %s "
+		       "for DIE at 0x%x [in module %s]"),
+		     paddress (gdbarch, part_die->lowpc),
+		     paddress (gdbarch, part_die->highpc),
+		     part_die->offset, cu->objfile->name);
+	}
+      else
+	part_die->has_pc_info = 1;
+    }
 
   return info_ptr;
 }

gdb/testsuite/ChangeLog

@@ -1,3 +1,13 @@
+2011-03-15  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+	* gdb.dwarf2/dw2-empty-pc-range.S: New file.
+	* gdb.dwarf2/dw2-empty-pc-range.exp: New file.
+	* gdb.dwarf2/pr11465.S: New .text labels text_start and text_end.
+	Provide a stub byte there.
+	(DW_TAG_compile_unit): Set DW_AT_low_pc, DW_AT_high_pc and
+	DW_AT_entry_pc.
+	(dieb4, dieda): Set DW_AT_high_pc higher than DW_AT_low_pc.
+
 2011-03-15  Ulrich Weigand  <uweigand@de.ibm.com>
 
 	* gdb.arch/altivec-abi.exp: Skip "generic" tests on 64-bit when

gdb/testsuite/gdb.dwarf2/dw2-empty-pc-range.S

@@ -0,0 +1,82 @@
+/* Copyright 2011, 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 <http://www.gnu.org/licenses/>.  */
+
+	.text
+pc_start:
+	.byte	0
+pc_end:
+
+	.section	.debug_info
+d:
+	.long	.Ldebug_info_end - 1f	/* Length of Compilation Unit Info */
+1:
+	.2byte	0x3	/* DWARF version number */
+	.long	.Ldebug_abbrev0	/* Offset Into Abbrev. Section */
+	.byte	0x4	/* Pointer Size (in bytes) */
+dieb:
+	.uleb128 0x1	/* (DIE (0xb) DW_TAG_compile_unit) */
+	.ascii	"GCC\0"	/* DW_AT_producer */
+	.byte	0x2	/* DW_AT_language = DW_LANG_C */
+	.ascii	"1.c\0"	/* DW_AT_name */
+
+	.uleb128 0x2		/* (DIE (0xd3) DW_TAG_subprogram) */
+	.byte	0x1		/* DW_AT_external */
+	.ascii	"realrange\0"	/* DW_AT_name */
+	.4byte	pc_start	/* DW_AT_low_pc */
+	.4byte	pc_end		/* DW_AT_high_pc */
+	.byte	0x1		/* DW_AT_prototyped */
+
+	.uleb128 0x2		/* (DIE (0xd3) DW_TAG_subprogram) */
+	.byte	0x1		/* DW_AT_external */
+	.ascii	"emptyrange\0"	/* DW_AT_name */
+	.4byte	pc_start	/* DW_AT_low_pc */
+	.4byte	pc_start	/* DW_AT_high_pc */
+	.byte	0x1		/* DW_AT_prototyped */
+
+	.byte	0x0	/* end of children of DIE 0xb */
+.Ldebug_info_end:
+
+	.section	.debug_abbrev
+.Ldebug_abbrev0:
+
+	.uleb128 0x1	/* (abbrev code) */
+	.uleb128 0x11	/* (TAG: DW_TAG_compile_unit) */
+	.byte	0x1	/* DW_children_yes */
+	.uleb128 0x25	/* (DW_AT_producer) */
+	.uleb128 0x8	/* (DW_FORM_string) */
+	.uleb128 0x13	/* (DW_AT_language) */
+	.uleb128 0xb	/* (DW_FORM_data1) */
+	.uleb128 0x3	/* (DW_AT_name) */
+	.uleb128 0x8	/* (DW_FORM_string) */
+	.byte	0x0
+	.byte	0x0
+
+	.uleb128 0x2	/* (abbrev code) */
+	.uleb128 0x2e	/* (DW_TAG_subprogram) */
+	.byte	0x0	/* DW_children_no */
+	.uleb128 0x3f	/* (DW_AT_external) */
+	.uleb128 0xc	/* (DW_FORM_flag) */
+	.uleb128 0x3	/* (DW_AT_name) */
+	.uleb128 0x8	/* (DW_FORM_string) */
+	.uleb128 0x11	/* (DW_AT_low_pc) */
+	.uleb128 0x1	/* (DW_FORM_addr) */
+	.uleb128 0x12	/* (DW_AT_high_pc) */
+	.uleb128 0x1	/* (DW_FORM_addr) */
+	.uleb128 0x27	/* (DW_AT_prototyped) */
+	.uleb128 0xc	/* (DW_FORM_flag) */
+	.byte	0x0
+	.byte	0x0
+
+	.byte	0x0

gdb/testsuite/gdb.dwarf2/dw2-empty-pc-range.exp

@@ -0,0 +1,40 @@
+# 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 <http://www.gnu.org/licenses/>.
+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-empty-pc-range"
+set srcfile ${testfile}.S
+set executable ${testfile}.x
+set binfile ${objdir}/${subdir}/${executable}
+
+if  { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" object {}] != "" } {
+    return -1
+}
+
+clean_restart $executable
+gdb_test "ptype emptyrange" {No symbol "emptyrange" in current context\.} \
+	 "empty range before CU load"
+
+# Force loading the CU
+gdb_test "ptype realrange" {type = void \(void\)} \
+	 "valid range after CU load"
+
+gdb_test "ptype emptyrange" {No symbol "emptyrange" in current context\.} \
+	 "empty range after CU load"

gdb/testsuite/gdb.dwarf2/pr11465.S

@@ -36,7 +36,12 @@
 */
 
 	.text
-_ZN1N1cE:	
+text_start:
+_ZN1N1cE:
+	/* Valid function must have non-empty PC range.  */
+	.byte 0
+text_end:
+
 	.section	.debug_info
 d:
 	.long	.Ldebug_info_end - 1f /* Length of CU info */
@@ -49,9 +54,9 @@ dieb:	.uleb128 0x1		/* DW_TAG_compile_unit */
 	.byte	0x4		/* DW_AT_language */
 	.long	.LASF5		/* DW_AT_name */
 	.long	.LASF6		/* DW_AT_comp_dir */
-	.long	0x0		/* DW_AT_low_pc */
-	.long	0x0		/* DW_AT_high_pc */
-	.long	0x0		/* DW_AT_entry_pc */
+	.long	text_start	/* DW_AT_low_pc */
+	.long	text_end	/* DW_AT_high_pc */
+	.long	text_start	/* DW_AT_entry_pc */
 die29:	.uleb128 0x2		/* DW_TAG_namespace */
 	.string	"N"		/* DW_AT_name */
 die32:	.uleb128 0x3		/* DW_TAG_class_type */
@@ -112,7 +117,7 @@ dieaf:	.uleb128 0xe		/* DW_TAG_const_type */
 dieb4:	.uleb128 0xf		/* DW_TAG_subprogram */
 	.long	die95-d		/* DW_AT_abstract_origin */
 	.long	_ZN1N1cE	/* DW_AT_low_pc */
-	.long	_ZN1N1cE	/* DW_AT_high_pc */
+	.long	_ZN1N1cE + 1	/* DW_AT_high_pc */
 diec9:	.uleb128 0x10		/* DW_TAG_subprogram */
 	.long	die9f-d		/* DW_AT_abstract_origin */
 	.byte	2f-1f		/* DW_AT_location */
@@ -131,7 +136,7 @@ dieda:	.uleb128 0x11		/* DW_TAG_subprogram */
 	.long	.LASF8		/* DW_AT_name */
 	.long	dief2-d		/* DW_AT_type */
 	.long	_ZN1N1cE	/* DW_AT_low_pc */
-	.long	_ZN1N1cE	/* DW_AT_high_pc */
+	.long	_ZN1N1cE + 1	/* DW_AT_high_pc */
 dief2:	.uleb128 0x12		/* DW_TAG_base_type */
 	.byte	0x4		/* DW_AT_byte_size */
 	.byte	0x5		/* DW_AT_encoding */