Re: [patch] build-id .debug files load (like .gnu_debuglink)

Jan Kratochvil
2007-08-25T22:49:41Z

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On Fri, 24 Aug 2007 20:20:28 +0200, Daniel Jacobowitz wrote:
> On Fri, Aug 24, 2007 at 08:04:50PM +0200, Jan Kratochvil wrote:
...
> > This part may be questionable:
> > - debugfile = find_separate_debug_file (objfile);
> > + /* If the file has its own symbol tables it has no separate debug info. */
> > + if (objfile->psymtabs == NULL)
> > + debugfile = find_separate_debug_file (objfile);
...
> > Not sure if `PSYMTABS == NULL' is the right condition. According to my
> > experiments on GNU/Linux it should be correct.
>
> In some cases a library will be left with .symtab but not .debug_info;
> sometimes elfutils does this, also sometimes it is done deliberately
> for ld.so / libpthread.so so that the separate debug file is not
> necessary for minimal debugging to work.

You are right about the content of `/lib64/ld-linux-x86-64.so.2'.
Still in such case both `.dynsym' and `.symtab' gets read into MSYMBOLS but
PSYMTABS and SYMTABS are left forever NULL for the main executable (as there is
no .debug_info).

While I would still expect the former patch was right I changed it according to
your advice. It is definitely the safe way but with a tiny performance hit:

The reason of my check was that build-id (contrary to the debug-link) is always
present there, even for locally built unsplit files. With the patch attached
below GDB will try to open a separate debug file in /usr/lib/debug/.debug-id/
even for the unsplit files. This step did not happen with my former patch.

> We should either pass a flag down so that we know we're already
> looking at the separate debug file (more efficient, saves us the
> second search, more work to implement)

Chose this way as the intention of the whole patch is performance.
(Aware OBJF_DEBUG_FILE is not an OBJFILE flag - just an additional
SYMBOL_FILE_ADD_WITH_ADDRS_OR_OFFSETS parameter - but it may get one day useful
for later retrieval from OBJFILE.)

> > +/* Locate NT_GNU_BUILD_ID and return its content.
> > + Separate debuginfo files have corrupted PHDR but SHDR is correct there. */
> > +
> > +static struct build_id *
> > +build_id_bfd_shdr_get (bfd *abfd)
> > +{
> > + struct build_id *retval;
> > +
> > + if (!bfd_check_format (abfd, bfd_object)
> > + || bfd_get_flavour (abfd) != bfd_target_elf_flavour
> > + || elf_tdata (abfd)->build_id == NULL)
> > + return NULL;
> > +
> > + retval = xmalloc (sizeof *retval - 1 + elf_tdata (abfd)->build_id_size);
> > + retval->size = elf_tdata (abfd)->build_id_size;
> > + memcpy (retval->data, elf_tdata (abfd)->build_id, retval->size);
> > +
> > + return retval;
> > +}
>
> This function isn't doing anything with program headers or section
> headers now, maybe it should be renamed (and the comment doesn't need
> to talk about corrupted phdrs in that case).

Not agreed as the PHDR<->SHDR difference is important (there are issues about
it for readelf/eu-readelf - whether PHDR or SHDR should be chosen there).
But changed according to your advice.

> I believe the manual needs an update to mention the new search path.

I see now, sorry, implemented.

Thanks,
Jan

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2007-08-25 Jan Kratochvil <jan.kratochvil@redhat.com>

* Makefile.in (symfile.o): Update dependencies.
* objfiles.h (OBJF_DEBUG_FILE): New definition.
* symfile.c (symbol_file_add_with_addrs_or_offsets): Initialize the
DEBUGFILE variable. FIND_SEPARATE_DEBUG_FILE protected against loop by
setting OBJF_DEBUG_FILE for the first call.
(struct build_id): New structure.
(build_id_bfd_get, build_id_verify, build_id_to_debug_filename): New.
(find_separate_debug_file): New variable BUILD_ID.
Call BUILD_ID_BFD_GET with BUILD_ID_TO_DEBUG_FILENAME as the first try.

2007-08-25 Jan Kratochvil <jan.kratochvil@redhat.com>

* lib/gdb.exp (build_id_debug_filename_get): New function.
* gdb.base/sepdebug.exp: Reflect the changes in the heading comment.
Remove the generate DEBUG file for the future testcase runs.
New testcase for the NT_GNU_BUILD_ID retrieval.
Move the final testing step to ...
(test_different_dir): ... a new function.
New parameter XFAIL to XFAIL all the tests performed.
New parameter TEST_DIFFERENT_DIR parametrizing the directory.
New parameter TYPE to PF_PREFIX all the tests performed.

2007-08-25 Jan Kratochvil <jan.kratochvil@redhat.com>

* gdb.texinfo (Separate Debug Files): Included a BUILD ID description.
Enlisted BUILD ID to the debug file searching example.
Included a BUILD ID `.note.gnu.build-id' section description.
Updated/added the debug files splitting instructions for OBJCOPY.

--- gdb/Makefile.in 23 Aug 2007 20:33:48 -0000 1.929
+++ gdb/Makefile.in 25 Aug 2007 22:43:21 -0000
@@ -2731,7 +2731,7 @@ symfile.o: symfile.c $(defs_h) $(bfdlink
$(gdb_stabs_h) $(gdb_obstack_h) $(completer_h) $(bcache_h) \
$(hashtab_h) $(readline_h) $(gdb_assert_h) $(block_h) \
$(gdb_string_h) $(gdb_stat_h) $(observer_h) $(exec_h) \
- $(parser_defs_h) $(varobj_h)
+ $(parser_defs_h) $(varobj_h) $(elf_bfd_h)
symfile-mem.o: symfile-mem.c $(defs_h) $(symtab_h) $(gdbcore_h) \
$(objfiles_h) $(exceptions_h) $(gdbcmd_h) $(target_h) $(value_h) \
$(symfile_h) $(observer_h) $(auxv_h) $(elf_common_h)
--- gdb/objfiles.h 23 Aug 2007 18:08:36 -0000 1.46
+++ gdb/objfiles.h 25 Aug 2007 22:43:21 -0000
@@ -448,6 +448,11 @@ struct objfile

#define OBJF_USERLOADED (1 << 5) /* User loaded */

+/* We should not try to find by build-id the separate debug info file for the
+ same separate debug info file itself. */
+
+#define OBJF_DEBUG_FILE (1 << 6) /* Separate debug file */
+
/* The object file that the main symbol table was loaded from (e.g. the
argument to the "symbol-file" or "file" command). */

--- gdb/symfile.c 23 Aug 2007 18:08:39 -0000 1.190
+++ gdb/symfile.c 25 Aug 2007 22:43:21 -0000
@@ -51,6 +51,7 @@
#include "exec.h"
#include "parser-defs.h"
#include "varobj.h"
+#include "elf-bfd.h"

#include <sys/types.h>
#include <fcntl.h>
@@ -1017,7 +1018,7 @@ symbol_file_add_with_addrs_or_offsets (b
{
struct objfile *objfile;
struct partial_symtab *psymtab;
- char *debugfile;
+ char *debugfile = NULL;
struct section_addr_info *orig_addrs = NULL;
struct cleanup *my_cleanups;
const char *name = bfd_get_filename (abfd);
@@ -1081,18 +1082,21 @@ symbol_file_add_with_addrs_or_offsets (b
}
}

- debugfile = find_separate_debug_file (objfile);
+ if (!(flags & OBJF_DEBUG_FILE))
+ debugfile = find_separate_debug_file (objfile);
if (debugfile)
{
if (addrs != NULL)
{
objfile->separate_debug_objfile
- = symbol_file_add (debugfile, from_tty, orig_addrs, 0, flags);
+ = symbol_file_add (debugfile, from_tty, orig_addrs, 0,
+ flags | OBJF_DEBUG_FILE);
}
else
{
objfile->separate_debug_objfile
- = symbol_file_add (debugfile, from_tty, NULL, 0, flags);
+ = symbol_file_add (debugfile, from_tty, NULL, 0,
+ flags | OBJF_DEBUG_FILE);
}
objfile->separate_debug_objfile->separate_debug_objfile_backlink
= objfile;
@@ -1223,6 +1227,97 @@ symbol_file_clear (int from_tty)
printf_unfiltered (_("No symbol file now.\n"));
}

+struct build_id
+ {
+ size_t size;
+ gdb_byte data[1];
+ };
+
+/* Locate NT_GNU_BUILD_ID from ABFD and return its content. */
+
+static struct build_id *
+build_id_bfd_get (bfd *abfd)
+{
+ struct build_id *retval;
+
+ if (!bfd_check_format (abfd, bfd_object)
+ || bfd_get_flavour (abfd) != bfd_target_elf_flavour
+ || elf_tdata (abfd)->build_id == NULL)
+ return NULL;
+
+ retval = xmalloc (sizeof *retval - 1 + elf_tdata (abfd)->build_id_size);
+ retval->size = elf_tdata (abfd)->build_id_size;
+ memcpy (retval->data, elf_tdata (abfd)->build_id, retval->size);
+
+ return retval;
+}
+
+/* Return if FILENAME has NT_GNU_BUILD_ID matching the CHECK value. */
+
+static int
+build_id_verify (const char *filename, struct build_id *check)
+{
+ bfd *abfd;
+ struct build_id *found = NULL;
+ int retval = 0;
+
+ /* We expect to be silent on the non-existing files. */
+ abfd = bfd_openr (filename, gnutarget);
+ if (abfd == NULL)
+ return 0;
+
+ found = build_id_bfd_get (abfd);
+
+ if (found == NULL)
+ warning (_("File \"%s\" has no build-id, file skipped"), filename);
+ else if (found->size != check->size
+ || memcmp (found->data, check->data, found->size) != 0)
+ warning (_("File \"%s\" has a different build-id, file skipped"), filename);
+ else
+ retval = 1;
+
+ if (!bfd_close (abfd))
+ warning (_("cannot close \"%s\": %s"), filename,
+ bfd_errmsg (bfd_get_error ()));
+ return retval;
+}
+
+static char *
+build_id_to_debug_filename (struct build_id *build_id)
+{
+ char *link, *s, *retval = NULL;
+ gdb_byte *data = build_id->data;
+ size_t size = build_id->size;
+
+ /* DEBUG_FILE_DIRECTORY/.build-id/ab/cdef */
+ link = xmalloc (strlen (debug_file_directory) + (sizeof "/.build-id/" - 1) + 1
+ + 2 * size + (sizeof ".debug" - 1) + 1);
+ s = link + sprintf (link, "%s/.build-id/", debug_file_directory);
+ if (size > 0)
+ {
+ size--;
+ s += sprintf (s, "%02x", (unsigned) *data++);
+ }
+ if (size > 0)
+ *s++ = '/';
+ while (size-- > 0)
+ s += sprintf (s, "%02x", (unsigned) *data++);
+ strcpy (s, ".debug");
+
+ /* lrealpath() is expensive even for the usually non-existent files. */
+ if (access (link, F_OK) == 0)
+ retval = lrealpath (link);
+ xfree (link);
+
+ if (retval != NULL && !build_id_verify (retval, build_id))
+ {
+ xfree (retval);
+ retval = NULL;
+ }
+
+ return retval;
+}
+
static char *
get_debug_link_info (struct objfile *objfile, unsigned long *crc32_out)
{
@@ -1300,6 +1395,18 @@ find_separate_debug_file (struct objfile
bfd_size_type debuglink_size;
unsigned long crc32;
int i;
+ struct build_id *build_id;
+
+ build_id = build_id_bfd_get (objfile->obfd);
+ if (build_id != NULL)
+ {
+ char *build_id_name;
+
+ build_id_name = build_id_to_debug_filename (build_id);
+ free (build_id);
+ if (build_id_name != NULL)
+ return build_id_name;
+ }

basename = get_debug_link_info (objfile, &crc32);

--- gdb/doc/gdb.texinfo 21 Aug 2007 15:09:59 -0000 1.423
+++ gdb/doc/gdb.texinfo 25 Aug 2007 22:43:31 -0000
@@ -11902,18 +11902,32 @@ than the executable code itself --- some
information for their executables in separate files, which users can
install only when they need to debug a problem.

-If an executable's debugging information has been extracted to a
-separate file, the executable should contain a @dfn{debug link} giving
-the name of the debugging information file (with no directory
-components), and a checksum of its contents. (The exact form of a
-debug link is described below.) If the full name of the directory
-containing the executable is @var{execdir}, and the executable has a
-debug link that specifies the name @var{debugfile}, then @value{GDBN}
-will automatically search for the debugging information file in three
-places:
+There are two identificators how the separate debug file may be found:

@itemize @bullet
@item
+@dfn{debug link} is present only in the executable if its debug information has
+been split out. It is not present in the separate debug file. It provides the
+separate debug file filename, usually as @file{executable.debug}.
+@item
+@dfn{build id} is present in all the files (if the operating system supports
+it). The executable file and its separate debug file have the same unique
+@dfn{build id} content.
+@end itemize
+
+If the full name of the directory containing the executable is @var{execdir},
+the executable has a debug link that specifies the name @var{debugfile},
+@var{bu} is the first byte (two hexadecimal characters) of the build id
+content, @var{ild-id} are the remaining bytes / hexadecimal characters and
+@var{globaldebugdir} is the global debug file directory then @value{GDBN} will
+automatically search for the debugging information file in four places:
+
+@itemize @bullet
+@item
+a specific file in the subdirectory of the global debug file directory
+according to the @dfn{build id} content (if present), the file tried is
+@file{@var{globaldebugdir}/.debug-id/@var{bu}/@var{ild-id}.debug}.
+@item
the directory containing the executable file (that is, it will look
for a file named @file{@var{execdir}/@var{debugfile}},
@item
@@ -11928,15 +11942,17 @@ executable's full path, and the name fro
@end itemize
@noindent
@value{GDBN} checks under each of these names for a debugging
-information file whose checksum matches that given in the link, and
-reads the debugging information from the first one it finds.
-
-So, for example, if you ask @value{GDBN} to debug @file{/usr/bin/ls},
-which has a link containing the name @file{ls.debug}, and the global
-debug directory is @file{/usr/lib/debug}, then @value{GDBN} will look
-for debug information in @file{/usr/bin/ls.debug},
-@file{/usr/bin/.debug/ls.debug}, and
-@file{/usr/lib/debug/usr/bin/ls.debug}.
+information file with build id content matching the build id content of the
+executable file - or - whose checksum matches the one given in the link in the
+debug link case. In each case @value{GDBN} reads the debugging information
+from the first debug file it finds.
+
+So, for example, if you ask @value{GDBN} to debug @file{/usr/bin/ls}, which has
+a @dfn{debug link} containing the name @file{ls.debug}, its @dfn{build id}
+value in hexadecimal is @code{abcdef} and the global debug directory is
+@file{/usr/lib/debug}, then @value{GDBN} will look for debug information in
+@file{/usr/lib/debug/.build-id/ab/cdef.debug}, @file{/usr/bin/ls.debug},
+@file{/usr/bin/.debug/ls.debug}, and @file{/usr/lib/debug/usr/bin/ls.debug}.

You can set the global debugging info directory's name, and view the
name @value{GDBN} is currently using.
@@ -11978,6 +11994,16 @@ Any executable file format can carry a d
contain a section named @code{.gnu_debuglink} with the contents
described above.

+@cindex @code{.note.gnu.build-id} sections
+@cindex build id
+Build id is a special section of the executable file named
+@code{.note.gnu.build-id}. The section contains unique identification hash
+derived from the built files - it remains the same across multiple builds of
+the same build tree. The default algorithm SHA1 produces 160 bits (40
+hexadecimal characters) of the content. The same section and value is present
+in the original built binary with symbols, in its stripped variant and in the
+separate debug information file.
+
The debugging information file itself should be an ordinary
executable, containing a full set of linker symbols, sections, and
debugging information. The sections of the debugging information file
@@ -11985,18 +12011,21 @@ should have the same names, addresses an
but they need not contain any data --- much like a @code{.bss} section
in an ordinary executable.

-As of December 2002, there is no standard GNU utility to produce
-separated executable / debugging information file pairs. Ulrich
-Drepper's @file{elfutils} package, starting with version 0.53,
-contains a version of the @code{strip} command such that the command
-@kbd{strip foo -f foo.debug} removes the debugging information from
-the executable file @file{foo}, places it in the file
-@file{foo.debug}, and leaves behind a debug link in @file{foo}.
-
-Since there are many different ways to compute CRC's (different
-polynomials, reversals, byte ordering, etc.), the simplest way to
-describe the CRC used in @code{.gnu_debuglink} sections is to give the
-complete code for a function that computes it:
+@sc{gnu} binary utilities contain the @samp{objcopy} utility able to produce
+the separated executable / debugging information file pairs by commands
+@kbd{objcopy --only-keep-debug foo foo.debug; strip -g foo; objcopy
+--add-gnu-debuglink="foo.debug" "foo"}. These commands remove the debugging
+information from the executable file @file{foo}, place it in the file
+@file{foo.debug}, and leave behind a debug link in @file{foo}. Ulrich
+Drepper's @file{elfutils} package, starting with version 0.53, contains
+a version of the @code{strip} command such that the command @kbd{strip foo -f
+foo.debug} has the same functionality as the three commands above.
+
+Since there are many different ways to compute CRC's for the debug link
+(different polynomials, reversals, byte ordering, etc.). This computation does
+not apply to the build id section. The simplest way to describe the CRC used
+in @code{.gnu_debuglink} sections is to give the complete code for a function
+that computes it:

@kindex gnu_debuglink_crc32
@smallexample
--- gdb/testsuite/gdb.base/sepdebug.exp 23 Aug 2007 18:14:17 -0000 1.8
+++ gdb/testsuite/gdb.base/sepdebug.exp 25 Aug 2007 22:43:31 -0000
@@ -19,11 +19,14 @@

# Based on break.exp, written by Rob Savoye. (rob@cygnus.com)
# Modified to test gdb's handling of separate debug info files.
+# Modified to test gdb's handling of a debug-id retrieval.

# This file has two parts. The first is testing that gdb behaves
# normally after reading in an executable and its corresponding
# separate debug file. The second moves the .debug file to a different
# location and tests the "set debug-file-directory" command.
+# The third is for testing build-id retrievel by finding the separate
+# ".debug-id/ab/cdef.debug" file.

if $tracelevel then {
@@ -828,93 +831,152 @@ test_next_with_recursion

#********

-# now move the .debug file to a different location so that we can test
-# the "set debug-file-directory" command.
-
-remote_exec build "mv ${objdir}/${subdir}/.debug/${testfile}.debug ${objdir}/${subdir}"
-gdb_exit
-gdb_start
-gdb_reinitialize_dir $srcdir/$subdir
-gdb_test "set debug-file-directory ${objdir}/${subdir}" ".*" "set separate debug location"
-gdb_load ${binfile}
+proc test_different_dir {type test_different_dir xfail} {
+ global srcdir subdir objdir binfile srcfile timeout gdb_prompt
+ global pf_prefix
+ global bp_location6 decimal hex
+
+ set pf_prefix "$type:"
+
+ gdb_exit
+ gdb_start
+ gdb_reinitialize_dir $srcdir/$subdir
+ gdb_test "set debug-file-directory ${test_different_dir}" ".*" "set separate debug location"
+ gdb_load ${binfile}

-if [target_info exists gdb_stub] {
- gdb_step_for_stub;
-}
+ if [target_info exists gdb_stub] {
+ gdb_step_for_stub;
+ }

-#
-# test break at function
-#
-gdb_test "break main" \
- "Breakpoint.*at.* file .*$srcfile, line.*" \
- "breakpoint function, optimized file"
+ #
+ # test break at function
+ #
+ if {$xfail} {
+ setup_xfail "*-*-*"
+ }
+ gdb_test "break main" \
+ "Breakpoint.*at.* file .*$srcfile, line.*" \
+ "breakpoint function, optimized file"

-#
-# test break at function
-#
-gdb_test "break marker4" \
- "Breakpoint.*at.* file .*$srcfile, line.*" \
- "breakpoint small function, optimized file"
+ #
+ # test break at function
+ #
+ if {$xfail} {
+ setup_xfail "*-*-*"
+ }
+ gdb_test "break marker4" \
+ "Breakpoint.*at.* file .*$srcfile, line.*" \
+ "breakpoint small function, optimized file"

-#
-# run until the breakpoint at main is hit. For non-stubs-using targets.
-#
-gdb_run_cmd
-gdb_expect {
- -re "Breakpoint \[0-9\]+,.*main .*argc.*argv.* at .*$srcfile:$bp_location6.*$bp_location6\[\t \]+if .argc.* \{.*$gdb_prompt $" {
- pass "run until function breakpoint, optimized file"
+ #
+ # run until the breakpoint at main is hit. For non-stubs-using targets.
+ #
+ gdb_run_cmd
+ if {$xfail} {
+ setup_xfail "*-*-*"
}
- -re "Breakpoint \[0-9\]+,.*main .*argc.*argv.* at .*$gdb_prompt $" {
- pass "run until function breakpoint, optimized file (code motion)"
+ gdb_expect {
+ -re "Breakpoint \[0-9\]+,.*main .*argc.*argv.* at .*$srcfile:$bp_location6.*$bp_location6\[\t \]+if .argc.* \{.*$gdb_prompt $" {
+ pass "run until function breakpoint, optimized file"
+ }
+ -re "Breakpoint \[0-9\]+,.*main .*argc.*argv.* at .*$gdb_prompt $" {
+ pass "run until function breakpoint, optimized file (code motion)"
+ }
+ -re "$gdb_prompt $" {
+ fail "run until function breakpoint, optimized file"
+ }
+ timeout {
+ fail "run until function breakpoint, optimized file (timeout)"
+ }
}
- -re "$gdb_prompt $" {
- fail "run until function breakpoint, optimized file"
+
+ #
+ # run until the breakpoint at a small function
+ #
+
+ #
+ # Add a second pass pattern. The behavior differs here between stabs
+ # and dwarf for one-line functions. Stabs preserves two line symbols
+ # (one before the prologue and one after) with the same line number,
+ # but dwarf regards these as duplicates and discards one of them.
+ # Therefore the address after the prologue (where the breakpoint is)
+ # has no exactly matching line symbol, and GDB reports the breakpoint
+ # as if it were in the middle of a line rather than at the beginning.
+
+ set bp_location13 [gdb_get_line_number "set breakpoint 13 here"]
+ set bp_location14 [gdb_get_line_number "set breakpoint 14 here"]
+ send_gdb "continue\n"
+ if {$xfail} {
+ setup_xfail "*-*-*"
}
- timeout {
- fail "run until function breakpoint, optimized file (timeout)"
+ gdb_expect {
+ -re "Breakpoint $decimal, marker4 \\(d=177601976\\) at .*$srcfile:$bp_location13\[\r\n\]+$bp_location13\[\t \]+void marker4.*" {
+ pass "run until breakpoint set at small function, optimized file"
+ }
+ -re "Breakpoint $decimal, $hex in marker4 \\(d=177601976\\) at .*$srcfile:$bp_location13\[\r\n\]+$bp_location13\[\t \]+void marker4.*" {
+ pass "run until breakpoint set at small function, optimized file"
+ }
+ -re "Breakpoint $decimal, marker4 \\(d=177601976\\) at .*$srcfile:$bp_location14\[\r\n\]+$bp_location14\[\t \]+void marker4.*" {
+ # marker4() is defined at line 46 when compiled with -DPROTOTYPES
+ pass "run until breakpoint set at small function, optimized file (line bp_location14)"
+ }
+ -re ".*$gdb_prompt " {
+ fail "run until breakpoint set at small function, optimized file"
+ }
+ timeout {
+ fail "run until breakpoint set at small function, optimized file (timeout)"
+ }
+ }
+
+
+ # Reset the default arguments for VxWorks
+ if [istarget "*-*-vxworks*"] {
+ set timeout 10
+ verbose "Timeout is now $timeout seconds" 2
+ send_gdb "set args main\n"
+ gdb_expect -re ".*$gdb_prompt $" {}
}
+
+ unset pf_prefix
+# proc test_different_dir
}

-#
-# run until the breakpoint at a small function
-#

-#
-# Add a second pass pattern. The behavior differs here between stabs
-# and dwarf for one-line functions. Stabs preserves two line symbols
-# (one before the prologue and one after) with the same line number,
-# but dwarf regards these as duplicates and discards one of them.
-# Therefore the address after the prologue (where the breakpoint is)
-# has no exactly matching line symbol, and GDB reports the breakpoint
-# as if it were in the middle of a line rather than at the beginning.
+# now move the .debug file to a different location so that we can test
+# the "set debug-file-directory" command.
+
+remote_exec build "mv ${objdir}/${subdir}/.debug/${testfile}.debug ${objdir}/${subdir}"
+set debugfile "${objdir}/${subdir}/${testfile}.debug"

-set bp_location13 [gdb_get_line_number "set breakpoint 13 here"]
-set bp_location14 [gdb_get_line_number "set breakpoint 14 here"]
-send_gdb "continue\n"
-gdb_expect {
- -re "Breakpoint $decimal, marker4 \\(d=177601976\\) at .*$srcfile:$bp_location13\[\r\n\]+$bp_location13\[\t \]+void marker4.*" {
- pass "run until breakpoint set at small function, optimized file"
- }
- -re "Breakpoint $decimal, $hex in marker4 \\(d=177601976\\) at .*$srcfile:$bp_location13\[\r\n\]+$bp_location13\[\t \]+void marker4.*" {
- pass "run until breakpoint set at small function, optimized file"
- }
- -re "Breakpoint $decimal, marker4 \\(d=177601976\\) at .*$srcfile:$bp_location14\[\r\n\]+$bp_location14\[\t \]+void marker4.*" {
- # marker4() is defined at line 46 when compiled with -DPROTOTYPES
- pass "run until breakpoint set at small function, optimized file (line bp_location14)"
- }
- -re ".*$gdb_prompt " {
- fail "run until breakpoint set at small function, optimized file"
- }
- timeout {
- fail "run until breakpoint set at small function, optimized file (timeout)"
+test_different_dir debuglink "${objdir}/${subdir}" 0
+
+
+# NT_GNU_BUILD_ID / .note.gnu.build-id test:
+
+set build_id_debug_filename [build_id_debug_filename_get $binfile]
+if {$build_id_debug_filename eq ""} {
+ unsupported "build-id is not supported by the compiler"
+
+ # Spare debug files may confuse testsuite runs in the future.
+ remote_exec build "rm -f $debugfile"
+} else {
+ set build_id_debugself_filename [build_id_debug_filename_get $debugfile]
+ set test "build-id support by binutils"
+ set xfail 0
+ if {$build_id_debugself_filename eq ""} {
+ unsupported $test
+ set xfail 1
+ } elseif {$build_id_debugself_filename ne $build_id_debug_filename} {
+ fail $test
+ } else {
+ pass $test
}
-}

+ file mkdir [file dirname ${objdir}/${subdir}/${build_id_debug_filename}]
+ remote_exec build "mv $debugfile ${objdir}/${subdir}/${build_id_debug_filename}"
+
+ test_different_dir build-id "${objdir}/${subdir}" $xfail

-# Reset the default arguments for VxWorks
-if [istarget "*-*-vxworks*"] {
- set timeout 10
- verbose "Timeout is now $timeout seconds" 2
- send_gdb "set args main\n"
- gdb_expect -re ".*$gdb_prompt $" {}
+ # Spare debug files may confuse testsuite runs in the future.
+ remote_exec build "rm -f ${objdir}/${subdir}/${build_id_debug_filename}"
}
--- gdb/testsuite/lib/gdb.exp 23 Aug 2007 20:10:04 -0000 1.86
+++ gdb/testsuite/lib/gdb.exp 25 Aug 2007 22:43:32 -0000
@@ -2482,6 +2482,27 @@ proc separate_debug_filename { exec } {
return $debug_file
}

+# Return the build-id hex string (usually 160 bits as 40 hex characters)
+# converted to the form: .build-id/ab/cdef1234...89.debug
+# Return "" if no build-id found.
+proc build_id_debug_filename_get { exec } {
+ set tmp "${exec}-tmp"
+ exec objcopy -j .note.gnu.build-id -O binary $exec $tmp
+ set fi [open $tmp]
+ # Skip the NOTE header.
+ read $fi 16
+ set data [read $fi]
+ close $fi
+ file delete $tmp
+ if {$data eq ""} {
+ return ""
+ }
+ # Convert it to hex.
+ binary scan $data H* data
+ set data [regsub {^..} $data {\0/}]
+ return ".build-id/${data}.debug";
+}
+
# Create stripped files for DEST, replacing it. If ARGS is passed, it is a
# list of optional flags. The only currently supported flag is no-main,
# which removes the symbol entry for main from the separate debug file.