[Bug python/14513] New: setting extended-prompt triggers spurious newline to be emitted

[vapier at gentoo dot org]

http://sourceware.org/bugzilla/show_bug.cgi?id=14513

Bug #: 14513
Summary: setting extended-prompt triggers spurious newline to
be emitted
Product: gdb
Version: HEAD
Status: NEW
Severity: minor
Priority: P2
Component: python
AssignedTo: ***@sourceware.org
ReportedBy: ***@gentoo.org
Classification: Unclassified


$ gdb -nx -q
(gdb) set extended-prompt (gdb-new)

(gdb-new)

what's with that newline after the set command ? if i do the same thing with
my .gdbinit:
set extended-prompt (gdb-new)

when i launch gdb, i get:
$ gdb -q

(gdb-new)

looking at the code, it appears to be coming from python/py-param.c's
get_set_value:
fprintf_filtered (gdb_stdout, "%s\n", set_doc_string);

the set_doc_string here is empty, so we just get an empty newline printed out.

i've never looked through the python code before to suggest a suitable fix ...

[tromey at redhat dot com]

http://sourceware.org/bugzilla/show_bug.cgi?id=14513

Tom Tromey <tromey at redhat dot com> changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |tromey at redhat dot com

--- Comment #1 from Tom Tromey <tromey at redhat dot com> 2012-08-24 18:20:11 UTC ---
That code seems bogus to me.
I don't understand why it ought to print anything at all.

[pmuldoon at redhat dot com]

http://sourceware.org/bugzilla/show_bug.cgi?id=14513

Phil Muldoon <pmuldoon at redhat dot com> changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |pmuldoon at redhat dot com
Assignee|unassigned at sourceware dot org |pmuldoon at redhat dot com

[seb93250 at gmail dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=14513

seb93250 at gmail dot com changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |seb93250 at gmail dot com

[tromey at sourceware dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=14513

Tom Tromey <tromey at sourceware dot org> changed:

What |Removed |Added
----------------------------------------------------------------------------
CC| |tromey at sourceware dot org

--- Comment #2 from Tom Tromey <tromey at sourceware dot org> ---
The discussion in late 2013 seems to have petered out.

I've been using this locally:

diff --git a/gdb/python/py-param.c b/gdb/python/py-param.c
index 06b9ae9..b395f9d 100644
--- a/gdb/python/py-param.c
+++ b/gdb/python/py-param.c
@@ -387,8 +387,12 @@ get_set_value (char *args, int from_tty,
set_doc_string = get_doc_string (obj, set_doc_cst);
}

+#if 0
+ /* See https://sourceware.org/bugzilla/show_bug.cgi?id=14513.
+ There's no reason to print anything here. */
make_cleanup (xfree, set_doc_string);
fprintf_filtered (gdb_stdout, "%s\n", set_doc_string);
+#endif

Py_XDECREF (set_doc_func);
do_cleanups (cleanup);

[tromey at sourceware dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=14513

--- Comment #3 from Tom Tromey <tromey at sourceware dot org> ---

Post by tromey at sourceware dot org
+#if 0
+ /* See https://sourceware.org/bugzilla/show_bug.cgi?id=14513.
+ There's no reason to print anything here. */
make_cleanup (xfree, set_doc_string);

Though of course the #if should come after making the cleanup.

[tromey at sourceware dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=14513

Tom Tromey <tromey at sourceware dot org> changed:

What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
Resolution|--- |FIXED

--- Comment #4 from Tom Tromey <tromey at sourceware dot org> ---
This was finally fixed by commit 984ee559a26e138d8bcc1f850c1cacb9eded2b1c.