This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.
gdb/ChangeLog:
Update copyright year range in all GDB files.
Jan pointed out in
<https://sourceware.org/ml/gdb-patches/2014-07/msg00553.html> that
these testcases have racy results:
gdb.base/double-prompt-target-event-error.exp
gdb.base/paginate-after-ctrl-c-running.exp
gdb.base/paginate-bg-execution.exp
gdb.base/paginate-execution-startup.exp
gdb.base/paginate-inferior-exit.exp
This is easily reproducible with "read1" from:
[reproducer for races of expect incomplete reads]
http://sourceware.org/bugzilla/show_bug.cgi?id=12649
The '-notransfer -re "<return>" { exp_continue }' trick in the current
tests doesn't actually work.
The issue that led to the -notransfer trick was that
"---Type <return> to continue, or q <return> to quit---"
has two "<return>"s. If one wants gdb_test_multiple to not hit the
built-in "<return>" match that results in FAIL, one has to expect the
pagination prompt in chunks, first up to the first "<return>", then
again, up to the second. Something around these lines:
gdb_test_multiple "" $test {
-re "<return>" {
exp_continue
}
-re "to quit ---" {
pass $test
}
}
The intent was for -notransfer+exp_continue to make expect fetch more
input, and rerun the matches against the now potentially fuller
buffer, and then eventually the -re that includes the full pagination
prompt regex would match instead (because it's listed higher up, it
would match first). But, once that "<return>" -notransfer -re
matches, it keeps re-matching forever. It seems like with
exp_continue, expect immediately retries matching, instead of first
reading in more data into the buffer, if available.
Fix this like I should have done in the first place. There's actually
no good reason for gdb_test_multiple to only match "<return>". We can
make gdb_test_multiple expect the whole pagination prompt text
instead, which is store in the 'pagination_prompt' global (similar to
'gdb_prompt'). Then a gdb_test_multiple caller that doesn't want the
default match to trigger, because it wants to see one pagination
prompt, does simply:
gdb_test_multiple "" $test {
-re "$pagination_prompt$" {
pass $test
}
}
which is just like when we don't want the default $gdb_prompt match
within gdb_test_multiple to trigger, like:
gdb_test_multiple "" $test {
-re "$gdb_prompt $" {
pass $test
}
}
Tested on x86_64 Fedora 20. In addition, I've let the racy tests run
all in parallel in a loop for 30 minutes, and they never failed.
gdb/testsuite/
2014-07-25 Pedro Alves <palves@redhat.com>
* gdb.base/double-prompt-target-event-error.exp
(cancel_pagination_in_target_event): Remove '-notransfer <return>'
match.
(cancel_pagination_in_target_event): Rework double prompt
detection.
* gdb.base/paginate-after-ctrl-c-running.exp
(test_ctrlc_while_target_running_paginates): Remove '-notransfer
<return>' match.
* gdb.base/paginate-bg-execution.exp
(test_bg_execution_pagination_return)
(test_bg_execution_pagination_cancel): Remove '-notransfer
<return>' matches.
* gdb.base/paginate-execution-startup.exp
(test_fg_execution_pagination_return)
(test_fg_execution_pagination_cancel): Remove '-notransfer
<return>' matches.
* gdb.base/paginate-inferior-exit.exp
(test_paginate_inferior_exited): Remove '-notransfer <return>'
match.
* lib/gdb-utils.exp (string_to_regexp): Move here from lib/gdb.exp.
* lib/gdb.exp (pagination_prompt): Run text through
string_to_regexp.
(gdb_test_multiple): Match $pagination_prompt instead of
"<return>".
(string_to_regexp): Move to lib/gdb-utils.exp.
If a pagination prompt triggers while the target is running, and the
target exits before the user responded to the pagination query, this
happens:
Starting program: foo
---Type <return> to continue, or q <return> to quit---No unwaited-for children left.
Couldn't get registers: No such process.
Couldn't get registers: No such process.
Couldn't get registers: No such process.
(gdb) Couldn't get registers: No such process.
(gdb)
To reiterate, the user hasn't replied to the pagination prompt above.
A pagination query nests an event loop (in gdb_readline_wrapper). In
async mode, in addition to stdin and signal handlers, we'll have the
target also installed in the event loop still. So if the target
reports an event, that wakes up the nested event loop, which calls
into fetch_inferior_event etc. to handle the event which generates
further output, all while we should be waiting for pagination
confirmation...
(TBC, any target event that generates output ends up spuriously waking
up the pagination, though exits seem to be the worse kind.)
I've played with a couple different approaches to fixing this, while
at the same time trying to avoid being invasive. Both revolve around
not listening to target events while in a pagination prompt (doing
anything else I think would be a much bigger change).
The approach taken just removes the target from the event loop while
within gdb_readline_wrapper. The other approach used gdb_select
directly, with only input_fd installed, but that had the issue that it
didn't handle the async signal handlers, and turned out to be a bit
more code than the first version.
gdb/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* top.c: Include "inf-loop.h".
(struct gdb_readline_wrapper_cleanup) <target_is_async_orig>: New
field.
(gdb_readline_wrapper_cleanup): Make the target async again, if it
was async before.
(gdb_readline_wrapper): Store whether the target is async, and
make it sync.
gdb/testsuite/
2014-07-14 Pedro Alves <palves@redhat.com>
PR gdb/17072
* gdb.base/paginate-inferior-exit.c: New file.
* gdb.base/paginate-inferior-exit.exp: New file.
Joel Brobecker
Luis Machado
Pedro Alves