Please define thread_info as struct thread_info (and other stuff)
Commit Message
Hi!
On Mon, 17 Dec 2018 13:41:25 -0800, John Baldwin <jhb@FreeBSD.org> wrote:
> On 12/17/18 12:51 PM, Svante Signell wrote:
> > On Sun, 2018-12-16 at 16:10 -0700, Tom Tromey wrote:
> >>>>>>> "Svante" == Svante Signell <svante.signell@gmail.com> writes:
> >> Svante> Finally, I've found the problem (but no workaround yet): thread_info
> >> is an RPC on GNU/Hurd, and including mach.h in gdb/config/i386/nm-
> >> i386gnu.h:#include <mach.h> further includes <mach/mach_interface.h> which has
> >> the conflicting name Svante> of that RPC: kern_return_t thread_info
> >>
> >> Typical answers for this kind of thing are either to segregate the use
> >> of the system header somehow, or maybe namespacing or some other kind of
> >> renaming. I haven't looked into the details much in this case I'm
> >> afraid.
> >
> > As I see it you need to:
> >
> > 1) Apply the patches submitted earlier in this thread using struct thread_info
> > consistently everywhere (simplest).
(We probably wouldn't be able to do that: necessary to work around some
compiler bug, I've seen a number of commits that changed "new-style C++
for iterators" away from 'for (struct thread_info *ti : [something])' to
just 'thread_info *ti' (without 'class' or 'struct').)
> > 2) Rename all usage of the struct thread_info to something else e.g. struct
> > gdb_thread_info (not future-proof though).
> > 3) Create a gdb namespace for all your code to avoid conflicts.
> > 4) Segregate the use of system header files as you write above. Dunno how to do
> > that though, but some of you should.
>
> Normally code for native targets do 4). I've had to be careful about which
> includes I use in native FreeBSD targets to avoid namespace collisions, etc.
Right. I have now pushed to master the attached commit
cabb5f067daa9227bf0323cbf64c6065d6e4796f "[gdb, hurd] Work around
conflict between Mach's 'thread_info' function, and GDB's 'thread_info'
class".
Grüße
Thomas
From cabb5f067daa9227bf0323cbf64c6065d6e4796f Mon Sep 17 00:00:00 2001
From: Thomas Schwinge <thomas@codesourcery.com>
Date: Wed, 13 Feb 2019 12:02:20 +0100
Subject: [PATCH] [gdb, hurd] Work around conflict between Mach's 'thread_info'
function, and GDB's 'thread_info' class
In file included from ./nm.h:25:0,
from [...]/gdb/defs.h:423,
from [...]/gdb/gdb.c:19:
[...]/gdb/regcache.h:35:46: warning: 'get_thread_regcache' initialized and declared 'extern'
extern struct regcache *get_thread_regcache (thread_info *thread);
^~~~~~~~~~~
[...]/gdb/regcache.h:35:46: error: 'regcache* get_thread_regcache' redeclared as different kind of symbol
[...]
[...]/gdb/gdbarch.h:1203:69: error: 'thread_info' is not a type
extern LONGEST gdbarch_get_syscall_number (struct gdbarch *gdbarch, thread_info *thread);
^~~~~~~~~~~
Fixed with a different (self-contained, more maintainable?) approach compared
to what has been done in commit 7aabaf9d4ad52a1df1f551908fbd8cafc5e7597a
"Create private_thread_info hierarchy", and commit
75cbc781e371279f4403045be93b07fd8fe7fde5 "gdb: For macOS, s/thread_info/struct
thread_info/". We don't want to change all the GDB code to everywhere use
'class thread_info' or 'struct thread_info' instead of plain 'thread_info'.
gdb/
* config/i386/nm-i386gnu.h: Don't "#include" any files.
* gnu-nat.h (mach_thread_info): New function.
* gnu-nat.c (thread_takeover_sc_cmd): Use it.
---
gdb/ChangeLog | 4 ++++
gdb/config/i386/nm-i386gnu.h | 5 -----
gdb/gnu-nat.c | 9 ++++++---
gdb/gnu-nat.h | 15 ++++++++++++++-
gdb/i386-gnu-nat.c | 4 +++-
5 files changed, 27 insertions(+), 10 deletions(-)
@@ -1,5 +1,9 @@
2019-02-14 Thomas Schwinge <thomas@codesourcery.com>
+ * config/i386/nm-i386gnu.h: Don't "#include" any files.
+ * gnu-nat.h (mach_thread_info): New function.
+ * gnu-nat.c (thread_takeover_sc_cmd): Use it.
+
* config/i386/nm-i386gnu.h (gnu_target_pid_to_str): Remove.
2019-02-14 Frederic Konrad <konrad@adacore.com>
@@ -19,11 +19,6 @@
#ifndef CONFIG_I386_NM_I386GNU_H
#define CONFIG_I386_NM_I386GNU_H
-#include <unistd.h>
-#include <mach.h>
-#include <mach/exception.h>
-#include "regcache.h"
-
/* Thread flavors used in re-setting the T bit. */
#define THREAD_STATE_FLAVOR i386_REGS_SEGS_STATE
#define THREAD_STATE_SIZE i386_THREAD_STATE_COUNT
@@ -20,6 +20,9 @@
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
+/* Include this first, to pick up the <mach.h> 'thread_info' diversion. */
+#include "gnu-nat.h"
+
/* Mach/Hurd headers are not yet ready for C++ compilation. */
extern "C"
{
@@ -67,7 +70,6 @@ extern "C"
#include "gdb_obstack.h"
#include "tid-parse.h"
-#include "gnu-nat.h"
#include "inf-child.h"
/* MIG stubs are not yet ready for C++ compilation. */
@@ -3429,8 +3431,9 @@ thread_takeover_sc_cmd (const char *args, int from_tty)
thread_basic_info_data_t _info;
thread_basic_info_t info = &_info;
mach_msg_type_number_t info_len = THREAD_BASIC_INFO_COUNT;
- kern_return_t err =
- thread_info (thread->port, THREAD_BASIC_INFO, (int *) &info, &info_len);
+ kern_return_t err
+ = mach_thread_info (thread->port, THREAD_BASIC_INFO,
+ (int *) &info, &info_len);
if (err)
error (("%s."), safe_strerror (err));
thread->sc = info->suspend_count;
@@ -19,8 +19,21 @@
#ifndef GNU_NAT_H
#define GNU_NAT_H
-#include <unistd.h>
+#include "defs.h"
+
+/* Work around conflict between Mach's 'thread_info' function, and GDB's
+ 'thread_info' class. Make the former available as 'mach_thread_info'. */
+#define thread_info mach_thread_info
+/* Mach headers are not yet ready for C++ compilation. */
+extern "C"
+{
#include <mach.h>
+}
+#undef thread_info
+/* Divert 'mach_thread_info' to the original Mach 'thread_info' function. */
+extern __typeof__ (mach_thread_info) mach_thread_info asm ("thread_info");
+
+#include <unistd.h>
struct inf;
@@ -17,6 +17,9 @@
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
+/* Include this first, to pick up the <mach.h> 'thread_info' diversion. */
+#include "gnu-nat.h"
+
/* Mach/Hurd headers are not yet ready for C++ compilation. */
extern "C"
{
@@ -34,7 +37,6 @@ extern "C"
#include "i386-tdep.h"
-#include "gnu-nat.h"
#include "inf-child.h"
#include "i387-tdep.h"
--
2.19.2