[patch] Fix internal error on library without dirname

[Jan Kratochvil <jan dot kratochvil at redhat dot com>]

Hi,

in some special cases ld.so can provide library name without any slash (/).

Starting program: [...]
../../gdb/symfile.c:1326: internal-error: find_separate_debug_file_by_debuglink: Assertion `i >= 0 && IS_DIR_SEPARATOR (dir[i])' failed.
A problem internal to GDB has been detected,

No regressions on {x86_64,x86_64-m32,i686}-fedora13-linux-gnu.

I believe it could go for 7.2.

I tried to step through find_separate_debug_file_by_debuglink in this case and
the code seems OK with DIR eq "".


Thanks,
Jan


gdb/
2010-07-20  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* symfile.c (find_separate_debug_file_by_debuglink): Remove
	a gdb_assert call, new comment.

gdb/testsuite/
2010-07-20  Jan Kratochvil  <jan.kratochvil@redhat.com>

	* gdb.base/solib-nodir.exp: New file.
	* lib/gdb.exp (runto): New case for a GDB internal error.

--- a/gdb/symfile.c
+++ b/gdb/symfile.c
@@ -1382,7 +1382,7 @@ find_separate_debug_file_by_debuglink (struct objfile *objfile)
       if (IS_DIR_SEPARATOR (dir[i]))
 	break;
     }
-  gdb_assert (i >= 0 && IS_DIR_SEPARATOR (dir[i]));
+  /* If I is -1 then no directory is present there and DIR will be "".  */
   dir[i+1] = '\0';
 
   /* Set I to max (strlen (canon_name), strlen (dir)). */
--- /dev/null
+++ b/gdb/testsuite/gdb.base/solib-nodir.exp
@@ -0,0 +1,54 @@
+# Copyright 2010 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/>.  */
+
+# are we on a target board
+if {![isnative] || [skip_shlib_tests]} {
+    return
+}
+
+set testfile "solib-nodir"
+# Arbitrary file, possibly not containing main, even an empty one.
+set srclibfile foo.c
+# Arbitrary file containing main.
+set srcfile start.c
+set binlibfilebase ${testfile}.so
+set binlibfiledir ${objdir}/${subdir}
+set binlibfile ${binlibfiledir}/${binlibfilebase}
+set executable ${testfile}
+set objfile ${objdir}/${subdir}/${executable}.o
+set binfile ${objdir}/${subdir}/${executable}
+
+# build the first test case
+if { [get_compiler_info unused]
+     || [gdb_compile_shlib "${srcdir}/${subdir}/${srclibfile}" "${binlibfile}" [list debug additional_flags=-Wl,-soname,${binlibfilebase}]] != ""
+     || [gdb_gnu_strip_debug $binlibfile]
+     || [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${objfile}" object {debug}] != ""
+     || [gdb_compile "${objfile} ${binlibfile}" "${binfile}" executable {}] != "" } {
+    untested ${testfile}.exp
+    return -1
+}
+
+clean_restart $executable
+gdb_load_shlibs ${binlibfile}
+
+gdb_test_no_output "set env LD_LIBRARY_PATH=:"
+gdb_test "cd ${binlibfiledir}" "Working directory [string_to_regexp ${binlibfiledir}]\\."
+
+set test "library loaded"
+if [runto_main] {
+    pass $test
+} else {
+    fail $test
+}
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -423,6 +423,11 @@ proc runto { function args } {
 	    unsupported "Non-stop mode not supported"
 	    return 0
 	}
+	-re ".*A problem internal to GDB has been detected" {
+	    fail "running to $function in runto (GDB internal error)"
+	    gdb_internal_error_resync
+	    return 0
+	}
 	-re "$gdb_prompt $" { 
 	    fail "running to $function in runto"
 	    return 0