File gdb-testsuite-fix-gdb.reverse-time-reverse.exp-timeo.patch of Package gdb
From dfe2f3417cbb50c46d4ecf5905615613511a7f72 Mon Sep 17 00:00:00 2001
From: Tom de Vries <tdevries@suse.de>
Date: Fri, 2 May 2025 16:48:14 +0200
Subject: [PATCH 3/6] [gdb/testsuite] Fix gdb.reverse/time-reverse.exp timeout
After building gdb with "-O0 -g -fsanitize=thread" on aarch64-linux, with
test-case gdb.reverse/time-reverse.exp I run into:
...
(gdb) continue^M
Continuing.^M
FAIL: $exp: mode=c: continue to breakpoint: marker2 (timeout)
...
The problem is that instruction stepping gets stuck in a loop with this call
stack: time -> __GI___clock_gettime -> __kernel_clock_gettime ->
__cvdso_clock_gettime.
This is not specific to fsanitize=thread, it just makes gdb slow, which makes
instruction stepping slow, which results in the application getting stuck.
I ran into this as well with a regular gdb build on a 32-bit i686 laptop with
1GB of memory, an inherently slow setup. In that instance, I was able to
observe that the loop we're stuck in is the outer loop in do_coarse in linux
kernel source lib/vdso/gettimeofday.c.
Fix this by setting "record full insn-number-max" to 2000, and handling
running into the limit.
Initially I tried the approach of using "stepi 2000" instead of continue, but
that made the issue more likely to show up (for instance, I observed it after
building gdb with -O0 on aarch64-linux).
Tested on aarch64-linux.
Approved-By: Guinevere Larsen <guinevere@redhat.com>
PR testsuite/32678
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=32678
---
gdb/testsuite/gdb.reverse/time-reverse.exp | 26 +++++++++++++++++++++-
1 file changed, 25 insertions(+), 1 deletion(-)
diff --git a/gdb/testsuite/gdb.reverse/time-reverse.exp b/gdb/testsuite/gdb.reverse/time-reverse.exp
index 98085f0ebc9..5a77fcd09f5 100644
--- a/gdb/testsuite/gdb.reverse/time-reverse.exp
+++ b/gdb/testsuite/gdb.reverse/time-reverse.exp
@@ -45,6 +45,8 @@ proc test {mode} {
# Activate process record/replay
gdb_test_no_output "record" "turn on process record"
+ gdb_test_no_output "set record full stop-at-limit on"
+ gdb_test_no_output "set record full insn-number-max 2000"
set re_srcfile [string_to_regexp $::srcfile]
@@ -52,7 +54,29 @@ proc test {mode} {
"Breakpoint $::decimal at $::hex: file .*$re_srcfile, line $::decimal.*" \
"set breakpoint at marker2"
- gdb_continue_to_breakpoint "marker2" ".*$re_srcfile:.*"
+ set re_question \
+ [string_list_to_regexp \
+ "Do you want to auto delete previous execution log entries when" \
+ " record/replay buffer becomes full" \
+ { (record full stop-at-limit)?([y] or n)}]
+ set re_program_stopped \
+ [multi_line \
+ [string_to_regexp "Process record: stopped by user."] \
+ "" \
+ [string_to_regexp "Program stopped."]]
+ set re_marker2 [string_to_regexp "marker2 ()"]
+ gdb_test_multiple "continue" "continue to breakpoint: marker2" {
+ -re "$re_question " {
+ send_gdb "n\n"
+ exp_continue
+ }
+ -re -wrap "Breakpoint $::decimal, $re_marker2 .*" {
+ pass $gdb_test_name
+ }
+ -re -wrap "\r\n$re_program_stopped\r\n.*" {
+ unsupported $gdb_test_name
+ }
+ }
# Show how many instructions we've recorded.
gdb_test "info record" "Active record target: .*"
--
2.43.0