Re: RFA: libunwind basic support

["J. Johnston" <jjohnstn@redhat.com>]

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Patch resubmitted.  See comments below.


Andrew Cagney wrote:
> 
>>> +#define STRINGIFY2(name)    #name
>>> +#define STRINGIFY(name)        STRINGIFY2(name)
>>> +
>>> +static char *get_reg_name = STRINGIFY(UNW_OBJ(get_reg));
>>> +static char *get_fpreg_name = STRINGIFY(UNW_OBJ(get_fpreg));
>>> +static char *get_saveloc_name = STRINGIFY(UNW_OBJ(get_saveloc));
>>> +static char *step_name = STRINGIFY(UNW_OBJ(step));
>>> +static char *init_remote_name = STRINGIFY(UNW_OBJ(init_remote));
>>> +static char *create_addr_space_name = 
>>> STRINGIFY(UNW_OBJ(create_addr_space));
>>> +static char *search_unwind_table_name = 
>>> STRINGIFY(UNW_OBJ(search_unwind_table));
>>> +static char *find_dyn_list_name = STRINGIFY(UNW_OBJ(find_dyn_list));
>>>
>>> I don't understand this.  A guess is that UNW_OBJ() is doing 
>>> something evil (use "include/sym-cat.h") to those names and having 
>>> the array (use "static const char <name>[] = ..." and local to 
>>> libunwind_load) makes ones debugging life much easier?  If this is 
>>> the case, can you add some commentary?
> 
> 
>> Yes.  The libunwind code is slightly ugly with respect to the fact 
>> that the function names are not aliased with generic names.  They all 
>> have platform prefixes so I must spell them out.  Function names are 
>> generated automatically using the UNW_OBJ macro.
> 
> 
> Can you please add this to the file as a comment.
> 

Done.

> 
> 
>> +void
>> +libunwind_frame_set_descr (struct gdbarch *gdbarch, struct 
>> libunwind_descr *descr)
>> +{
>> +  struct libunwind_descr *arch_descr;
>> +
>> +  gdb_assert (gdbarch != NULL);
>> +
>> +  arch_descr = gdbarch_data (gdbarch, libunwind_descr_handle);
>> +
>> +  if (arch_descr == NULL)
>> +    {
>> +      /* First time here.  Must initialize data area.  */
>> +      arch_descr = libunwind_descr_init (gdbarch);
>> +      set_gdbarch_data (gdbarch, libunwind_descr_handle, arch_descr);
>> +    }
>> +
>> +  /* Copy new descriptor info into arch descriptor.  */
>> +  arch_descr->gdb2uw = descr->gdb2uw;
>> +  arch_descr->uw2gdb = descr->uw2gdb;
>> +  arch_descr->is_fpreg = descr->is_fpreg;
>> +  arch_descr->accessors = descr->accessors;
>> +}
> 
> 
> Yes!  Now the architecture has-a libunwind structure.
> 
> Doesn't the configury make this:
> 
>> +#ifdef HAVE_LIBUNWIND_H
> 
> 
> redundant?
>

It is possible for the user to enable libunwind but the header files are not 
there.  I am guessing you would prefer compilation to fail in this case so I 
have removed the check.

>> +  libunwind_descr_handle = register_gdbarch_data (libunwind_descr_init);
>> +
>> +  libunwind_initialized = libunwind_load ();
>> +#endif  
> 
> 
>> +   Contributed by Jeff Johnston.
> 
> 
> (redhat)
> 

Changed.

> 
>> +const struct frame_unwind *libunwind_frame_sniffer (struct frame_info 
>> *next_frame);
> 
> 
> Comments for this one ...
> 

Done.

>> +void libunwind_frame_set_descr (struct gdbarch *arch, struct 
>> libunwind_descr *descr);
>> +
>> +void libunwind_frame_this_id (struct frame_info *next_frame, void 
>> **this_cache,
>> +                  struct frame_id *this_id);
>> +void libunwind_frame_prev_register (struct frame_info *next_frame, 
>> void **this_cache,
>> +                    int regnum, int *optimizedp,
>> +                    enum lval_type *lvalp, CORE_ADDR *addrp,
>> +                    int *realnump, void *valuep);
>> +CORE_ADDR libunwind_frame_base_address (struct frame_info 
>> *next_frame, void **this_cache);
>> +
>> +int libunwind_is_initialized (void);
>> +
>> +int libunwind_search_unwind_table (void *as, long ip, void *di,
>> +                   void *pi, int need_unwind_info, void *args);
> 
> 
> Also comments for this one ...
> 

I have added comments for the search unwind table call.

>> +unw_word_t libunwind_find_dyn_list (unw_addr_space_t, void *, size_t,
>> +                    unw_word_t, unw_word_t, void *);
> 
> 
>> Index: Makefile.in
> 
> 
> Yep.
> 
>> +    libunwind-frame.c \
> 
> 
>> -    $(elf_bfd_h) $(dis_asm_h)
>> +    $(elf_bfd_h) $(dis_asm_h) $(libunwind_frame_h)
> 
> 
>> +libunwind-frame.o: libunwind-frame.c $(defs_h) \
>> +    $(frame_h) $(frame_base_h) $(frame_unwind_h) $(gdbcore_h) \
>> +    $(gdbtypes_h) $(symtab_h) $(objfiles_h) $(regcache_h) \
>> +    $(gdb_assert_h) $(gdb_string_h) $(complaints_h) $(libunwind_frame_h)
> 
> 
>> Index: configure.in
>> ===================================================================
>> RCS file: /cvs/src/src/gdb/configure.in,v
>> retrieving revision 1.132
>> diff -u -r1.132 configure.in
>> --- configure.in    3 Sep 2003 15:02:48 -0000    1.132
>> +++ configure.in    22 Oct 2003 23:36:21 -0000
>> @@ -192,6 +192,33 @@
>>      enable_gdbtk=no ;;
>>  esac
> 
> 
> Based on 12.1 Working With External Software
> http://www.gnu.org/software/autoconf/manual/autoconf-2.57/html_chapter/autoconf_12.html#SEC130 
> 
> 
> I suspect that this should be --with (external libunwind software), and 
> not --enable (gdb feature), although, to be honest, its hard to tell 
> which it should be.
> 
> Anyone?
>

 From discussions with Jeff Law when I was doing configuration for newlib, he 
told me that --enable should be used for on/off decisions in preference to 
--with.  I don't personally care so I have switched to --with.

>> +# Enable libunwind support.
>> +AC_ARG_ENABLE(libunwind,
>> +[  --enable-libunwind          enable libunwind frame unwinding 
>> support],
>> +  [case $enableval in
>> +    yes | no)
> 
> 
> The behavior should be:
> 
> --{with,enable}-libunwind
> Enable libunwind unconditionally.
> 
> --{without,disable}-libunwind
> Disable libunwind unconditionally
> 
>> +      ;;
>> +    *)
>> +      AC_MSG_ERROR([bad value $enableval for --enable-libunwind]) ;;
>> +  esac]
> 
> 
> <none>
> Check for "libunwind.h" and "libunwind-ia64.h" and if present, enable 
> it.  Something like:
>     AC_CHECK_HEADERS(libunwind.h)
>     AC_CHECK_HEADERS(libunwind-ia64.h)
>     test $ac_cv_have_libunwind_h = yes && enable_libunwind=yes
> 
> )
> 
> And then just:
> 
>> +  if test x"$enable_libunwind" = xyes; then
>> +    AC_CHECK_HEADERS(libunwind.h)
>> +    AC_CHECK_HEADERS(libunwind-ia64.h)
>> +    CONFIG_OBS="$CONFIG_OBS libunwind-frame.o"
>> +    CONFIG_DEPS="$CONFIG_DEPS libunwind-frame.o"
>> +    CONFIG_SRCS="$CONFIG_SRCS libunwind-frame.c"
> 
> 
> but also AC_DEFINE(HAVE_LIBUNWIND) so that it can be used.
> 

Done.



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Index: libunwind-frame.c
===================================================================
RCS file: libunwind-frame.c
diff -N libunwind-frame.c
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ libunwind-frame.c	13 Nov 2003 23:05:04 -0000
@@ -0,0 +1,388 @@
+/* Frame unwinder for frames using the libunwind library.
+
+   Copyright 2003 Free Software Foundation, Inc.
+
+   Written by Jeff Johnston, contributed by Red Hat 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.  */
+
+#include "defs.h"
+
+#include "inferior.h"
+#include "frame.h"
+#include "frame-base.h"
+#include "frame-unwind.h"
+#include "gdbcore.h"
+#include "gdbtypes.h"
+#include "symtab.h"
+#include "objfiles.h"
+#include "regcache.h"
+
+#include <dlfcn.h>
+
+#include "gdb_assert.h"
+#include "gdb_string.h"
+
+#include "libunwind-frame.h"
+
+#include "complaints.h"
+
+static int libunwind_initialized;
+static struct gdbarch_data *libunwind_descr_handle;
+
+#ifndef LIBUNWIND_SO
+#define LIBUNWIND_SO "libunwind.so"
+#endif
+
+/* Required function pointers from libunwind.  */
+static int (*unw_get_reg_p) (unw_cursor_t *, unw_regnum_t, unw_word_t *);
+static int (*unw_get_fpreg_p) (unw_cursor_t *, unw_regnum_t, unw_fpreg_t *);
+static int (*unw_get_saveloc_p) (unw_cursor_t *, unw_regnum_t, unw_save_loc_t *);
+static int (*unw_step_p) (unw_cursor_t *);
+static int (*unw_init_remote_p) (unw_cursor_t *, unw_addr_space_t, void *);
+static unw_addr_space_t (*unw_create_addr_space_p) (unw_accessors_t *, int);
+static int (*unw_search_unwind_table_p) (unw_addr_space_t, unw_word_t, unw_dyn_info_t *,
+					 unw_proc_info_t *, int, void *);
+static unw_word_t (*unw_find_dyn_list_p) (unw_addr_space_t, void *, size_t,
+					  unw_word_t, unw_word_t, void *);
+
+
+struct libunwind_frame_cache
+{
+  CORE_ADDR base;
+  CORE_ADDR func_addr;
+  unw_cursor_t cursor;
+};
+
+/* We need to qualify the function names with a platform-specific prefix to match 
+   the names used by the libunwind library.  The UNW_OBJ macro is provided by the
+   libunwind.h header file.  */
+#define STRINGIFY2(name)	#name
+#define STRINGIFY(name)		STRINGIFY2(name)
+
+static char *get_reg_name = STRINGIFY(UNW_OBJ(get_reg));
+static char *get_fpreg_name = STRINGIFY(UNW_OBJ(get_fpreg));
+static char *get_saveloc_name = STRINGIFY(UNW_OBJ(get_save_loc));
+static char *step_name = STRINGIFY(UNW_OBJ(step));
+static char *init_remote_name = STRINGIFY(UNW_OBJ(init_remote));
+static char *create_addr_space_name = STRINGIFY(UNW_OBJ(create_addr_space));
+static char *search_unwind_table_name = STRINGIFY(UNW_OBJ(search_unwind_table));
+static char *find_dyn_list_name = STRINGIFY(UNW_OBJ(find_dyn_list));
+
+static struct libunwind_descr *
+libunwind_descr (struct gdbarch *gdbarch)
+{
+  return gdbarch_data (gdbarch, libunwind_descr_handle);
+}
+
+static void *
+libunwind_descr_init (struct gdbarch *gdbarch)
+{
+  struct libunwind_descr *descr = GDBARCH_OBSTACK_ZALLOC (gdbarch,
+							  struct libunwind_descr);
+  return descr;
+}
+
+void
+libunwind_frame_set_descr (struct gdbarch *gdbarch, struct libunwind_descr *descr)
+{
+  struct libunwind_descr *arch_descr;
+
+  gdb_assert (gdbarch != NULL);
+
+  arch_descr = gdbarch_data (gdbarch, libunwind_descr_handle);
+
+  if (arch_descr == NULL)
+    {
+      /* First time here.  Must initialize data area.  */
+      arch_descr = libunwind_descr_init (gdbarch);
+      set_gdbarch_data (gdbarch, libunwind_descr_handle, arch_descr);
+    }
+
+  /* Copy new descriptor info into arch descriptor.  */
+  arch_descr->gdb2uw = descr->gdb2uw;
+  arch_descr->uw2gdb = descr->uw2gdb;
+  arch_descr->is_fpreg = descr->is_fpreg;
+  arch_descr->accessors = descr->accessors;
+}
+
+static struct libunwind_frame_cache *
+libunwind_frame_cache (struct frame_info *next_frame, void **this_cache)
+{
+  unw_accessors_t *acc;
+  unw_addr_space_t as;
+  unw_word_t fp;
+  unw_regnum_t uw_sp_regnum;
+  struct libunwind_frame_cache *cache;
+  struct libunwind_descr *descr;
+  int i, ret;
+
+  if (*this_cache)
+    return *this_cache;
+
+  /* Allocate a new cache.  */
+  cache = FRAME_OBSTACK_ZALLOC (struct libunwind_frame_cache);
+
+  cache->func_addr = frame_func_unwind (next_frame);
+
+  /* Get a libunwind cursor to the previous frame.  We do this by initializing
+     a cursor.  Libunwind treats a new cursor as the top of stack and will get
+     the current register set via the libunwind register accessor.  Now, we
+     provide the platform-specific accessors and we set up the register accessor to use
+     the frame register unwinding interfaces so that we properly get the registers for
+     the current frame rather than the top.  We then use the  unw_step function to 
+     move the libunwind cursor back one frame.  We can later use this cursor to find previous 
+     registers via the unw_get_reg interface which will invoke libunwind's special logic.  */
+  descr = libunwind_descr (get_frame_arch (next_frame));
+  acc = descr->accessors;
+  as =  unw_create_addr_space_p (acc,
+				 TARGET_BYTE_ORDER == BFD_ENDIAN_BIG
+				 ? __BIG_ENDIAN
+				 : __LITTLE_ENDIAN);
+
+  unw_init_remote_p (&cache->cursor, as, next_frame);
+  unw_step_p (&cache->cursor);
+
+  /* To get base address, get sp from previous frame.  */
+  uw_sp_regnum = descr->gdb2uw (SP_REGNUM);
+  ret = unw_get_reg_p (&cache->cursor, uw_sp_regnum, &fp);
+  if (ret < 0)
+    error ("Can't get libunwind sp register.");
+
+  cache->base = (CORE_ADDR)fp;
+
+  *this_cache = cache;
+  return cache;
+}
+
+unw_word_t 
+libunwind_find_dyn_list (unw_addr_space_t as, void *table, size_t table_size,
+			 unw_word_t segbase, unw_word_t gp, void *arg)
+{
+  return unw_find_dyn_list_p (as, table, table_size, segbase, gp, arg);
+}
+
+static const struct frame_unwind libunwind_frame_unwind =
+{
+  NORMAL_FRAME,
+  libunwind_frame_this_id,
+  libunwind_frame_prev_register
+};
+
+/* Verify if there is sufficient libunwind information for the frame to use
+   libunwind frame unwinding.  */
+const struct frame_unwind *
+libunwind_frame_sniffer (struct frame_info *next_frame)
+{
+  unw_cursor_t cursor;
+  unw_accessors_t *acc;
+  unw_addr_space_t as;
+  struct libunwind_descr *descr;
+  int i, ret;
+
+  /* To test for libunwind unwind support, initialize a cursor to the current frame and try to back
+     up.  We use this same method when setting up the frame cache (see libunwind_frame_cache()).
+     If libunwind returns success for this operation, it means that it has found sufficient
+     libunwind unwinding information to do so.  */
+
+  descr = libunwind_descr (get_frame_arch (next_frame));
+  acc = descr->accessors;
+  as =  unw_create_addr_space_p (acc,
+				 TARGET_BYTE_ORDER == BFD_ENDIAN_BIG
+				 ? __BIG_ENDIAN
+				 : __LITTLE_ENDIAN);
+
+  ret = unw_init_remote_p (&cursor, as, next_frame);
+
+  if (ret >= 0)
+    ret = unw_step_p (&cursor);
+
+  if (ret < 0)
+    return NULL;
+
+  return &libunwind_frame_unwind;
+}
+
+void
+libunwind_frame_this_id (struct frame_info *next_frame, void **this_cache,
+		      struct frame_id *this_id)
+{
+  struct libunwind_frame_cache *cache =
+    libunwind_frame_cache (next_frame, this_cache);
+
+  (*this_id) = frame_id_build (cache->base, cache->func_addr);
+}
+
+void
+libunwind_frame_prev_register (struct frame_info *next_frame, void **this_cache,
+			       int regnum, int *optimizedp,
+			       enum lval_type *lvalp, CORE_ADDR *addrp,
+			       int *realnump, void *valuep)
+{
+  struct libunwind_frame_cache *cache =
+    libunwind_frame_cache (next_frame, this_cache);
+
+  void *ptr;
+  unw_cursor_t *c;
+  unw_save_loc_t sl;
+  int i, ret;
+  unw_word_t intval;
+  unw_fpreg_t fpval;
+  unw_regnum_t uw_regnum;
+  struct libunwind_descr *descr;
+
+  /* Convert from gdb register number to libunwind register number.  */
+  descr = libunwind_descr (get_frame_arch (next_frame));
+  uw_regnum = descr->gdb2uw (regnum);
+
+  gdb_assert (regnum >= 0);
+
+  if (!target_has_registers)
+    error ("No registers.");
+
+  *optimizedp = 0;
+  *addrp = 0;
+  *lvalp = not_lval;
+  *realnump = -1;
+
+  memset (valuep, 0, register_size (current_gdbarch, regnum));
+
+  if (uw_regnum < 0)
+    return;
+
+  /* To get the previous register, we use the libunwind register APIs with
+     the cursor we have already pushed back to the previous frame.  */
+
+  if (descr->is_fpreg (uw_regnum))
+    {
+      ret = unw_get_fpreg_p (&cache->cursor, uw_regnum, &fpval);
+      ptr = &fpval;
+    }
+  else
+    {
+      ret = unw_get_reg_p (&cache->cursor, uw_regnum, &intval);
+      ptr = &intval;
+    }
+
+  if (ret < 0)
+    return;
+
+  memcpy (valuep, ptr, register_size (current_gdbarch, regnum));
+
+  if (unw_get_saveloc_p (&cache->cursor, uw_regnum, &sl) < 0)
+    return;
+
+  switch (sl.type)
+    {
+    case UNW_SLT_NONE:
+      *optimizedp = 1;
+      break;
+
+    case UNW_SLT_MEMORY:
+      *lvalp = lval_memory;
+      *addrp = sl.u.addr;
+      break;
+
+    case UNW_SLT_REG:
+      *lvalp = lval_register;
+      *realnump = regnum;
+      break;
+    }
+} 
+
+CORE_ADDR
+libunwind_frame_base_address (struct frame_info *next_frame, void **this_cache)
+{
+  struct libunwind_frame_cache *cache =
+    libunwind_frame_cache (next_frame, this_cache);
+
+  return cache->base;
+}
+
+/* The following is a glue routine to call the libunwind unwind table
+   search function to get unwind information for a specified ip address.  */ 
+int
+libunwind_search_unwind_table (void *as, long ip, void *di,
+			       void *pi, int need_unwind_info, void *args)
+{
+  return unw_search_unwind_table_p (*(unw_addr_space_t *)as, (unw_word_t )ip, 
+				    di, pi, need_unwind_info, args);
+}
+
+static int
+libunwind_load (void)
+{
+  void *handle;
+
+  handle = dlopen (LIBUNWIND_SO, RTLD_NOW);
+  if (handle == NULL)
+    return 0;
+
+  /* Initialize pointers to the dynamic library functions we will use.  */
+
+  unw_get_reg_p = dlsym (handle, get_reg_name);
+  if (unw_get_reg_p == NULL)
+    return 0;
+
+  unw_get_fpreg_p = dlsym (handle, get_fpreg_name);
+  if (unw_get_fpreg_p == NULL)
+    return 0;
+
+  unw_get_saveloc_p = dlsym (handle, get_saveloc_name);
+  if (unw_get_saveloc_p == NULL)
+    return 0;
+
+  unw_step_p = dlsym (handle, step_name);
+  if (unw_step_p == NULL)
+    return 0;
+
+  unw_init_remote_p = dlsym (handle, init_remote_name);
+  if (unw_init_remote_p == NULL)
+    return 0;
+
+  unw_create_addr_space_p = dlsym (handle, create_addr_space_name);
+  if (unw_create_addr_space_p == NULL)
+    return 0;
+
+  unw_search_unwind_table_p = dlsym (handle, search_unwind_table_name);
+  if (unw_search_unwind_table_p == NULL)
+    return 0;
+
+  unw_find_dyn_list_p = dlsym (handle, find_dyn_list_name);
+  if (unw_find_dyn_list_p == NULL)
+    return 0;
+   
+  return 1;
+}
+
+int
+libunwind_is_initialized (void)
+{
+  return libunwind_initialized;
+}
+
+/* Provide a prototype to silence -Wmissing-prototypes.  */
+void _initialize_libunwind_frame (void);
+
+void
+_initialize_libunwind_frame (void)
+{
+  libunwind_descr_handle = register_gdbarch_data (libunwind_descr_init);
+
+  libunwind_initialized = libunwind_load ();
+}
Index: libunwind-frame.h
===================================================================
RCS file: libunwind-frame.h
diff -N libunwind-frame.h
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ libunwind-frame.h	13 Nov 2003 23:05:04 -0000
@@ -0,0 +1,63 @@
+/* Frame unwinder for frames with libunwind frame information.
+
+   Copyright 2003 Free Software Foundation, Inc.
+
+   Contributed by Jeff Johnston.
+
+   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 HAVE_LIBUNWIND_H
+
+#ifndef LIBUNWIND_FRAME_H
+#define LIBUNWIND_FRAME_H 1
+
+#include "libunwind.h"
+
+struct frame_info;
+
+struct libunwind_descr
+{
+  int (*gdb2uw) (int);
+  int (*uw2gdb) (int);
+  int (*is_fpreg) (int);
+  void *accessors;
+};
+
+const struct frame_unwind *libunwind_frame_sniffer (struct frame_info *next_frame);
+
+void libunwind_frame_set_descr (struct gdbarch *arch, struct libunwind_descr *descr);
+
+void libunwind_frame_this_id (struct frame_info *next_frame, void **this_cache,
+			      struct frame_id *this_id);
+void libunwind_frame_prev_register (struct frame_info *next_frame, void **this_cache,
+				    int regnum, int *optimizedp,
+				    enum lval_type *lvalp, CORE_ADDR *addrp,
+				    int *realnump, void *valuep);
+CORE_ADDR libunwind_frame_base_address (struct frame_info *next_frame, void **this_cache);
+
+int libunwind_is_initialized (void);
+
+int libunwind_search_unwind_table (void *as, long ip, void *di,
+				   void *pi, int need_unwind_info, void *args);
+
+unw_word_t libunwind_find_dyn_list (unw_addr_space_t, void *, size_t,
+				    unw_word_t, unw_word_t, void *);
+     
+#endif /* libunwind-frame.h */
+
+#endif /* HAVE_LIBUNWIND_H  */
Index: Makefile.in
===================================================================
RCS file: /cvs/src/src/gdb/Makefile.in,v
retrieving revision 1.468
diff -u -r1.468 Makefile.in
--- Makefile.in	3 Nov 2003 17:03:11 -0000	1.468
+++ Makefile.in	13 Nov 2003 23:05:04 -0000
@@ -707,6 +707,7 @@
 jv_lang_h = jv-lang.h
 kod_h = kod.h
 language_h = language.h
+libunwind_frame_h = libunwind-frame.h
 linespec_h = linespec.h
 linux_nat_h = linux-nat.h
 m2_lang_h = m2-lang.h
@@ -1279,6 +1280,7 @@
 	i386gnu-nat.c i386gnu-tdep.c \
 	ia64-linux-nat.c ia64-linux-tdep.c ia64-tdep.c \
 	infptrace.c inftarg.c irix4-nat.c irix5-nat.c \
+	libunwind-frame.c \
 	lynx-nat.c m3-nat.c \
 	m68hc11-tdep.c \
 	m68k-tdep.c \
@@ -1910,7 +1912,7 @@
 	$(arch_utils_h) $(floatformat_h) $(regcache_h) $(reggroups_h) \
 	$(frame_h) $(frame_base_h) $(frame_unwind_h) $(doublest_h) \
 	$(value_h) $(gdb_assert_h) $(objfiles_h) $(elf_common_h) \
-	$(elf_bfd_h) $(dis_asm_h)
+	$(elf_bfd_h) $(dis_asm_h) $(libunwind_frame_h)
 infcall.o: infcall.c $(defs_h) $(breakpoint_h) $(target_h) $(regcache_h) \
 	$(inferior_h) $(gdb_assert_h) $(block_h) $(gdbcore_h) $(language_h) \
 	$(symfile_h) $(gdbcmd_h) $(command_h) $(gdb_string_h) $(infcall_h)
@@ -1958,6 +1960,10 @@
 language.o: language.c $(defs_h) $(gdb_string_h) $(symtab_h) $(gdbtypes_h) \
 	$(value_h) $(gdbcmd_h) $(expression_h) $(language_h) $(target_h) \
 	$(parser_defs_h) $(jv_lang_h) $(demangle_h)
+libunwind-frame.o: libunwind-frame.c $(defs_h) \
+	$(frame_h) $(frame_base_h) $(frame_unwind_h) $(gdbcore_h) \
+	$(gdbtypes_h) $(symtab_h) $(objfiles_h) $(regcache_h) \
+	$(gdb_assert_h) $(gdb_string_h) $(complaints_h) $(libunwind_frame_h)
 linespec.o: linespec.c $(defs_h) $(symtab_h) $(frame_h) $(command_h) \
 	$(symfile_h) $(objfiles_h) $(source_h) $(demangle_h) $(value_h) \
 	$(completer_h) $(cp_abi_h) $(parser_defs_h) $(block_h) \
Index: configure.in
===================================================================
RCS file: /cvs/src/src/gdb/configure.in,v
retrieving revision 1.132
diff -u -r1.132 configure.in
--- configure.in	3 Sep 2003 15:02:48 -0000	1.132
+++ configure.in	13 Nov 2003 23:05:05 -0000
@@ -192,6 +192,30 @@
     enable_gdbtk=no ;;
 esac
 
+# Libunwind support.
+AC_ARG_WITH(libunwind,
+[  --with-libunwind            Use libunwind frame unwinding support],
+[case "${withval}" in
+  yes)  enable_libunwind=yes ;;
+  no)   enable_libunwind=no ;;
+  *)    AC_MSG_ERROR(bad value ${withval} for GDB with-libunwind option) ;;
+esac],[
+  AC_CHECK_HEADERS(libunwind.h)
+  AC_CHECK_HEADERS(libunwind-ia64.h)
+  if test x"$ac_cv_header_libunwind_h" = xyes -a x"$ac_cv_header_libunwind_ia64_h" = xyes; then
+    enable_libunwind=yes;
+  fi
+])
+   
+if test x"$enable_libunwind" = xyes; then
+  AC_CHECK_HEADERS(libunwind.h)
+  AC_CHECK_HEADERS(libunwind-ia64.h)
+  AC_DEFINE(HAVE_LIBUNWIND, 1)
+  CONFIG_OBS="$CONFIG_OBS libunwind-frame.o"
+  CONFIG_DEPS="$CONFIG_DEPS libunwind-frame.o"
+  CONFIG_SRCS="$CONFIG_SRCS libunwind-frame.c"
+fi
+
 # Profiling support.
 AC_ARG_ENABLE(profiling,
 [  --enable-profiling      enable profiling of GDB],