gdb/

	Make core files the process_stratum.
	* corefile.c (core_target): New variable.
	(core_file_command): Remove variable t, use core_target.
	* corelow.c (core_ops): Make it static.
	(init_core_ops): Change to process_stratum.  Initialize CORE_TARGET.
	* defs.h (make_cleanup_unpush_target): New prototype.
	* gdbarch.h: Regenerate.
	* gdbarch.sh (core_pid_to_str): Remove core_stratum from its comment.
	* gdbcore.h (core_target): New declaration.
	* inf-ptrace.c (inf_ptrace_create_inferior, inf_ptrace_attach): New
	variables ops_already_pushed and back_to.  Use push_target,
	make_cleanup_unpush_target and discard_cleanups calls.
	* record.c (record_open): Replace core_stratum by a core_bfd check.
	* target.c (target_is_pushed): New function.
	(find_core_target): Remove.
	* target.h (enum strata) <core_stratum>: Remove.
	(target_is_pushed): New declaration.
	(find_core_target): Remove declaration.
	* tracepoint.c (init_tfile_ops) <to_stratum>: Remove comment.
	* utils.c (do_unpush_target, make_cleanup_unpush_target): New functions.

gdb/doc/
	Make core files the process_stratum.
	* gdb.texinfo (Active Targets): Remove core_stratum.  Include
	record_stratum example.

gdb/testsuite/
	Make core files the process_stratum.
	* gdb.base/corefile.exp (run: load core again)
	(run: sanity check we see the core file, run: with core)
	(run: core file is cleared, attach: load core again)
	(attach: sanity check we see the core file, attach: with core)
	(attach: core file is cleared): New tests.
	* gdb.base/coremaker.c (main): New parameters.  Implement "sleep" argv.

1 files changed, 29 insertions, 2 deletions

diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
index ba9d8a8aec9..82dfc343fc4 100644
--- a/gdb/inf-ptrace.c
+++ b/gdb/inf-ptrace.c
@@ -121,10 +121,23 @@ inf_ptrace_create_inferior (struct target_ops *ops,
 {
   int pid;
 
+  /* Do not change either targets above or the same target if already present.
+     The reason is the target stack is shared across multiple inferiors.  */
+  int ops_already_pushed = target_is_pushed (ops);
+  struct cleanup *back_to;
+
+  if (! ops_already_pushed)
+    {
+      /* Clear possible core file with its process_stratum.  */
+      push_target (ops);
+      back_to = make_cleanup_unpush_target (ops);
+    }
+
   pid = fork_inferior (exec_file, allargs, env, inf_ptrace_me, NULL,
 		       NULL, NULL);
 
-  push_target (ops);
+  if (! ops_already_pushed)
+    discard_cleanups (back_to);
 
   /* On some targets, there must be some explicit synchronization
      between the parent and child processes after the debugger
@@ -189,11 +202,24 @@ inf_ptrace_attach (struct target_ops *ops, char *args, int from_tty)
   pid_t pid;
   struct inferior *inf;
 
+  /* Do not change either targets above or the same target if already present.
+     The reason is the target stack is shared across multiple inferiors.  */
+  int ops_already_pushed = target_is_pushed (ops);
+  struct cleanup *back_to;
+
   pid = parse_pid_to_attach (args);
 
   if (pid == getpid ())		/* Trying to masturbate?  */
     error (_("I refuse to debug myself!"));
 
+  if (! ops_already_pushed)
+    {
+      /* target_pid_to_str already uses the target.  Also clear possible core
+	 file with its process_stratum.  */
+      push_target (ops);
+      back_to = make_cleanup_unpush_target (ops);
+    }
+
   if (from_tty)
     {
       exec_file = get_exec_file (0);
@@ -226,7 +252,8 @@ inf_ptrace_attach (struct target_ops *ops, char *args, int from_tty)
      target, it should decorate the ptid later with more info.  */
   add_thread_silent (inferior_ptid);
 
-  push_target(ops);
+  if (! ops_already_pushed)
+    discard_cleanups (back_to);
 }
 
 #ifdef PT_GET_PROCESS_STATE