[PATCH] use bind_lastarg to restore $_ when executing variable

[Emanuele Torre]

Before this patch, if allexport was set, $_ gained the "x" attribute
after PROMPT_COMMAND finished running, that would only get removed after
the next simple command is executed.

  $ PROMPT_COMMAND=:
  $ : foo
  $ declare -p _
  declare -- _="foo"
  $ set -a
  $ : bar
  $ declare -p _
  declare -x _="bar"
  $ : zoo; declare -p _; : bee
  declare -- _="zoo"
  $ declare -p _
  declare -x _="bee"
---
 execute_cmd.c | 3 +--
 execute_cmd.h | 2 ++
 parse.y       | 2 +-
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/execute_cmd.c b/execute_cmd.c
index d4c082d0..18540409 100644
--- a/execute_cmd.c
+++ b/execute_cmd.c
@@ -121,7 +121,6 @@ extern int close (int);
 /* Static functions defined and used in this file. */
 static void close_pipes (int, int);
 static void do_piping (int, int);
-static void bind_lastarg (char *);
 static int shell_control_structure (enum command_type);
 static void cleanup_redirects (REDIRECT *);
 
@@ -4000,7 +3999,7 @@ execute_cond_command (COND_COM *cond_command)
 }
 #endif /* COND_COMMAND */
 
-static void
+void
 bind_lastarg (char *arg)
 {
   SHELL_VAR *var;
diff --git a/execute_cmd.h b/execute_cmd.h
index 37e386ab..944b6a98 100644
--- a/execute_cmd.h
+++ b/execute_cmd.h
@@ -85,6 +85,8 @@ extern void dispose_exec_redirects (void);
 
 extern int execute_shell_function (SHELL_VAR *, WORD_LIST *);
 
+extern void bind_lastarg (char *);
+
 extern struct coproc *getcoprocbypid (pid_t);
 extern struct coproc *getcoprocbyname (const char *);
 
diff --git a/parse.y b/parse.y
index f5199f15..8db9bee6 100644
--- a/parse.y
+++ b/parse.y
@@ -2848,7 +2848,7 @@ execute_variable_command (const char *command, const char 
*vname)
   parse_and_execute (savestring (command), vname, 
SEVAL_NONINT|SEVAL_NOHIST|SEVAL_NOOPTIMIZE);
 
   restore_parser_state (&ps);
-  bind_variable ("_", last_lastarg, 0);
+  bind_lastarg (last_lastarg);
   FREE (last_lastarg);
 
   if (token_to_read == '\n')   /* reset_parser was called */
-- 
2.39.1