[RFC] Remove START_INFERIOR_TRAPS_EXPECTED macro from nm header

["Pierre Muller" <pierre.muller@ics-cnrs.unistra.fr>]

  This patch achieves the subject by
adding a new field to target_ops structure
called to_start_inferior_traps_expected.

  The changes are otherwise quite straightforward,
but once again, I have no way to even check that this
compiles for the different native GDB that it affects...

  Comments welcome,

Pierre Muller

2011-03-22  Pierre Muller  <muller@ics.u-strasbg.fr>

	Replace START_INFERIOR_TRAPS_EXPECTED macro by a new filed in
	target_ops struct named to_start_inferior_traps_expected.
	* config/alpha/alpha-osf3.mh: Set MH_CFLAGS to be able
	to set to_start_inferior_traps_expected correctly.
	config/alpha/nm-osf3.h: Remove START_INFERIOR_TRAPS_EXCEPTED macro.
	* target.h (struct target_ops): Add to_start_inferior_traps_expected
field.
	* target.c (update_current_target): Inherit field
	to_start_inferior_traps_expected for beneath and set default to 2.
	* alpha-nat.c (_initialize_alpha_nat): Set
	to_start_inferior_traps_expected to 3 if macro _STARTUP_INF_3_TRAPS.
	(darwin_ptrace_him): Use darwin_ops to_start_inferior_traps_expected
	field for startup_inferior parameter.
	* inf-ptrace.c (inf_ptrace_create_inferior): Adapt startup_inferior
	call using ops->toèstart_inferior_traps_expected.
	inf-ttrace.c (inf_ttrace_him): Ditto.
	* procfs.c (procfs_init_inferior): Ditto.

diff --git a/gdb/alpha-nat.c b/gdb/alpha-nat.c
index 1a55ea9..bb77035 100644
--- a/gdb/alpha-nat.c
+++ b/gdb/alpha-nat.c
@@ -197,6 +197,16 @@ _initialize_alpha_nat (void)
   struct target_ops *t;
 
   t = procfs_target ();
+
+  /* OSF-3 needs three traps.  */
+#ifdef _STARTUP_INF_3_TRAPS
+/* Number of traps that happen between exec'ing the shell
+   to run an inferior, and when we finally get to
+   the inferior code.  This is 2 on most implementations.  */
+/* was define START_INFERIOR_TRAPS_EXPECTED 3 */
+  t->to_start_inferior_traps_expected = 3;
+#endif
+
   add_target (t);
 
   deprecated_add_core_fns (&alpha_osf_core_fns);
diff --git a/gdb/config/alpha/alpha-osf3.mh b/gdb/config/alpha/alpha-osf3.mh
index 8dc6f80..1ef7195 100644
--- a/gdb/config/alpha/alpha-osf3.mh
+++ b/gdb/config/alpha/alpha-osf3.mh
@@ -1,5 +1,6 @@
 # Host: Little-endian Alpha running OSF/1-3.x and higher using procfs
 NAT_FILE= nm-osf3.h
+MH_CFLAGS=-D_STARTUP_INF_3_TRAPS
 NATDEPFILES= corelow.o alpha-nat.o fork-child.o \
 	solib-osf.o solib.o procfs.o proc-api.o proc-events.o proc-flags.o \
 	proc-why.o dec-thread.o
diff --git a/gdb/config/alpha/nm-osf3.h b/gdb/config/alpha/nm-osf3.h
index 626a497..56bf4d9 100644
--- a/gdb/config/alpha/nm-osf3.h
+++ b/gdb/config/alpha/nm-osf3.h
@@ -16,11 +16,6 @@
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
 
-/* Number of traps that happen between exec'ing the shell
-   to run an inferior, and when we finally get to
-   the inferior code.  This is 2 on most implementations.  */
-#define START_INFERIOR_TRAPS_EXPECTED 3
-
 /* Don't trace faults under OSF/1, rely on the posting of the appropriate
    signal if fault tracing is disabled.
    Tracing T_IFAULT under Alpha OSF/1 causes a `floating point enable'
diff --git a/gdb/darwin-nat.c b/gdb/darwin-nat.c
index 7be85d5..74c8b5a 100644
--- a/gdb/darwin-nat.c
+++ b/gdb/darwin-nat.c
@@ -1485,7 +1485,7 @@ darwin_ptrace_him (int pid)
 
   darwin_init_thread_list (inf);
 
-  startup_inferior (START_INFERIOR_TRAPS_EXPECTED);
+  startup_inferior (darwin_ops->to_start_inferior_traps_expected);
 }
 
 static void
diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
index b5e1744..0a3f776 100644
--- a/gdb/inf-ptrace.c
+++ b/gdb/inf-ptrace.c
@@ -142,7 +142,7 @@ inf_ptrace_create_inferior (struct target_ops *ops,
   /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h, and will
      be 1 or 2 depending on whether we're starting without or with a
      shell.  */
-  startup_inferior (START_INFERIOR_TRAPS_EXPECTED);
+  startup_inferior (ops->to_start_inferior_traps_expected);
 
   /* On some targets, there must be some explicit actions taken after
      the inferior has been started up.  */
diff --git a/gdb/inf-ttrace.c b/gdb/inf-ttrace.c
index ab075db..7b9ee2d 100644
--- a/gdb/inf-ttrace.c
+++ b/gdb/inf-ttrace.c
@@ -630,7 +630,7 @@ inf_ttrace_him (struct target_ops *ops, int pid)
   /* START_INFERIOR_TRAPS_EXPECTED is defined in inferior.h, and will
      be 1 or 2 depending on whether we're starting without or with a
      shell.  */
-  startup_inferior (START_INFERIOR_TRAPS_EXPECTED);
+  startup_inferior (ops->to_start_inferior_traps_expected);
 
   /* On some targets, there must be some explicit actions taken after
      the inferior has been started up.  */
diff --git a/gdb/procfs.c b/gdb/procfs.c
index 5d7cb23..467af2c 100644
--- a/gdb/procfs.c
+++ b/gdb/procfs.c
@@ -4710,7 +4710,7 @@ procfs_init_inferior (struct target_ops *ops, int pid)
 
   /* Typically two, one trap to exec the shell, one to exec the
      program being debugged.  Defined by "inferior.h".  */
-  startup_inferior (START_INFERIOR_TRAPS_EXPECTED);
+  startup_inferior (ops->to_start_inferior_traps_expected);
 
 #ifdef SYS_syssgi
   /* On mips-irix, we need to stop the inferior early enough during
diff --git a/gdb/target.c b/gdb/target.c
index 45259fd..3ab7248 100644
--- a/gdb/target.c
+++ b/gdb/target.c
@@ -677,6 +677,7 @@ update_current_target (void)
       INHERIT (to_static_tracepoint_marker_at, t);
       INHERIT (to_static_tracepoint_markers_by_strid, t);
       INHERIT (to_traceframe_info, t);
+      INHERIT (to_start_inferior_traps_expected, t);
       INHERIT (to_magic, t);
       /* Do not inherit to_memory_map.  */
       /* Do not inherit to_flash_erase.  */
@@ -886,6 +887,7 @@ update_current_target (void)
   de_fault (to_traceframe_info,
 	    (struct traceframe_info * (*) (void))
 	    tcomplain);
+  de_fault (to_start_inferior_traps_expected, 2);
 #undef de_fault
 
   /* Finally, position the target-stack beneath the squashed
diff --git a/gdb/target.h b/gdb/target.h
index 237d1aa..9842a0a 100644
--- a/gdb/target.h
+++ b/gdb/target.h
@@ -743,6 +743,9 @@ struct target_ops
        re-fetching when necessary.  */
     struct traceframe_info *(*to_traceframe_info) (void);
 
+    /* Number of traps expected at startup of target.  */
+    int to_start_inferior_traps_expected;
+
     int to_magic;
     /* Need sub-structure for target machine related rather than comm
related?
      */