From: Simon Marchi <simon.marchi@polymtl.ca>
To: gdb-patches@sourceware.org
Cc: Simon Marchi <simon.marchi@polymtl.ca>
Subject: [PATCH 2/7] gdb: add prepare_reinflate/reinflate around print_frame_args in info_frame_command_core
Date: Mon, 7 Nov 2022 10:53:05 -0500 [thread overview]
Message-ID: <20221107155310.2590069-2-simon.marchi@polymtl.ca> (raw)
In-Reply-To: <20221107155310.2590069-1-simon.marchi@polymtl.ca>
I noticed this crash:
$ ./gdb --data-directory=data-directory -nx -q \
testsuite/outputs/gdb.python/pretty-print-call-by-hand/pretty-print-call-by-hand \
-x testsuite/outputs/gdb.python/pretty-print-call-by-hand/pretty-print-call-by-hand.py \
-ex "b g" -ex r
(gdb) info frame
Stack level 0, frame at 0x7fffffffdd80:
rip = 0x555555555160 in g
(/home/simark/src/binutils-gdb/gdb/testsuite/gdb.python/pretty-print-call-by-hand.c:41); saved rip = 0x5555555551a3
called by frame at 0x7fffffffdda0
source language c.
Arglist at 0x7fffffffdd70, args: mt=mytype is 0x555555556004 "hello world",
depth=10
Fatal signal: Segmentation fault
This is another case of frame_info being invalidated under a function's
feet. The stack trace when the frame_info get invalidated looks like:
... many frames to pretty print the arg, that eventually invalidate the frame_infos ...
#35 0x00005568d0a8ab24 in print_frame_arg (fp_opts=..., arg=0x7ffc3216bcb0) at /home/simark/src/binutils-gdb/gdb/stack.c:489
#36 0x00005568d0a8cc75 in print_frame_args (fp_opts=..., func=0x621000233210, frame=..., num=-1, stream=0x60b000000300)
at /home/simark/src/binutils-gdb/gdb/stack.c:898
#37 0x00005568d0a9536d in info_frame_command_core (fi=..., selected_frame_p=true) at /home/simark/src/binutils-gdb/gdb/stack.c:1682
print_frame_args knows that print_frame_arg can invalidate frame_info
objects, and therefore calls prepare_reinflate/reinflate. However,
info_frame_command_core has a separate frame_info_ptr instance (it is
passed by value / copy). So info_frame_command_core needs to know that
print_frame_args can invalidate frame_info objects, and therefore needs
to prepare_reinflate/reinflate as well. Add those calls, and enhance
the gdb.python/pretty-print-call-by-hand.exp test to test that command.
Change-Id: I9edaae06d62e97ffdb30938d364437737238a960
---
gdb/stack.c | 4 ++++
gdb/testsuite/gdb.python/pretty-print-call-by-hand.exp | 8 ++++++++
2 files changed, 12 insertions(+)
diff --git a/gdb/stack.c b/gdb/stack.c
index 653251c200b4..4e2342c2a8d9 100644
--- a/gdb/stack.c
+++ b/gdb/stack.c
@@ -1679,8 +1679,12 @@ info_frame_command_core (frame_info_ptr fi, bool selected_frame_p)
else
gdb_printf (" %d args: ", numargs);
}
+
+ fi.prepare_reinflate ();
print_frame_args (user_frame_print_options,
func, fi, numargs, gdb_stdout);
+ fi.reinflate ();
+
gdb_puts ("\n");
}
}
diff --git a/gdb/testsuite/gdb.python/pretty-print-call-by-hand.exp b/gdb/testsuite/gdb.python/pretty-print-call-by-hand.exp
index 0aeb2218f911..eb3fc9e35faf 100644
--- a/gdb/testsuite/gdb.python/pretty-print-call-by-hand.exp
+++ b/gdb/testsuite/gdb.python/pretty-print-call-by-hand.exp
@@ -98,6 +98,14 @@ with_test_prefix "frame print" {
"backtrace test"
}
}
+
+# Test the "info frame" command
+with_test_prefix "info frame" {
+ if { [start_test "TAG: first frame"] == 0 } {
+ gdb_test "info frame" "mytype is $hex \"hello world\".*"
+ }
+}
+
# Testing the down command.
with_test_prefix "frame movement down" {
if { [start_test "TAG: first frame"] == 0 } {
--
2.38.1
next prev parent reply other threads:[~2022-11-07 15:53 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-07 15:53 [PATCH 1/7] gdb: clear other.m_cached_id in frame_info_ptr's move ctor Simon Marchi
2022-11-07 15:53 ` Simon Marchi [this message]
2022-11-08 9:32 ` [PATCH 2/7] gdb: add prepare_reinflate/reinflate around print_frame_args in info_frame_command_core Bruno Larsen
2022-11-08 15:55 ` Simon Marchi
2022-11-08 19:39 ` Tom Tromey
2022-11-08 19:55 ` Simon Marchi
2022-11-07 15:53 ` [PATCH 3/7] gdb: move frame_info_ptr method implementations to frame-info.c Simon Marchi
2022-11-08 9:55 ` Bruno Larsen
2022-11-08 17:39 ` Tom Tromey
2022-11-07 15:53 ` [PATCH 4/7] gdb: remove manual frame_info reinflation code in backtrace_command_1 Simon Marchi
2022-11-08 10:14 ` Bruno Larsen
2022-11-08 16:05 ` Simon Marchi
2022-11-07 15:53 ` [PATCH 5/7] gdb: use frame_id_p instead of comparing to null_frame_id in frame_info_ptr::reinflate Simon Marchi
2022-11-08 17:43 ` Tom Tromey
2022-11-07 15:53 ` [PATCH 6/7] gdb: add missing prepare_reinflate call in print_frame_info Simon Marchi
2022-11-08 10:28 ` Bruno Larsen
2022-11-08 11:31 ` Lancelot SIX
2022-11-08 16:08 ` Simon Marchi
2022-11-07 15:53 ` [PATCH 7/7] gdb: add special handling for frame level 0 in frame_info_ptr Simon Marchi
2022-11-08 10:40 ` Bruno Larsen
2022-11-08 16:19 ` Simon Marchi
2022-11-10 16:28 ` Bruno Larsen
2022-11-10 16:30 ` Simon Marchi
2022-11-08 8:53 ` [PATCH 1/7] gdb: clear other.m_cached_id in frame_info_ptr's move ctor Bruno Larsen
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