[PATCH] Use correct default for target functions that return pointer

[PATCH] Use correct default for target functions that return pointer

[Andreas Schwab]

It is wrong to use a function that returns an int as a placeholder for a
function that returns a pointer.

Andreas.

	* target.c (return_null): Define.
	(update_current_target): Use it instead of return_zero for
	functions that return a pointer.
---
 gdb/target.c | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/gdb/target.c b/gdb/target.c
index 65c7a7a..42a8741 100644
--- a/gdb/target.c
+++ b/gdb/target.c
@@ -64,6 +64,8 @@ static int return_one (void);
 
 static int return_minus_one (void);
 
+static void *return_null (void);
+
 void target_ignore (void);
 
 static void target_command (char *, int);
@@ -806,10 +808,10 @@ update_current_target (void)
 	    return_zero);
   de_fault (to_extra_thread_info,
 	    (char *(*) (struct thread_info *))
-	    return_zero);
+	    return_null);
   de_fault (to_thread_name,
 	    (char *(*) (struct thread_info *))
-	    return_zero);
+	    return_null);
   de_fault (to_stop,
 	    (void (*) (ptid_t))
 	    target_ignore);
@@ -819,7 +821,7 @@ update_current_target (void)
 	    tcomplain);
   de_fault (to_pid_to_exec_file,
 	    (char *(*) (int))
-	    return_zero);
+	    return_null);
   de_fault (to_async,
 	    (void (*) (void (*) (enum inferior_event_type, void*), void*))
 	    tcomplain);
@@ -918,7 +920,7 @@ update_current_target (void)
 	    tcomplain);
   de_fault (to_traceframe_info,
 	    (struct traceframe_info * (*) (void))
-	    return_zero);
+	    return_null);
   de_fault (to_supports_evaluation_of_breakpoint_conditions,
 	    (int (*) (void))
 	    return_zero);
@@ -3634,6 +3636,12 @@ return_minus_one (void)
   return -1;
 }
 
+static void *
+return_null (void)
+{
+  return 0;
+}
+
 /*
  * Find the next target down the stack from the specified target.
  */
-- 
1.8.5.2

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

Re: [PATCH] Use correct default for target functions that return pointer

[Tom Tromey]

>>>>> "Andreas" == Andreas Schwab <schwab@linux-m68k.org> writes:

Andreas> 	* target.c (return_null): Define.
Andreas> 	(update_current_target): Use it instead of return_zero for
Andreas> 	functions that return a pointer.

Ok.
FWIW I have a coming massive patch series that removes
nearly all uses of return_zero.  After the series there are few enough
uses that we can make this code truly type-safe.

Tom