File gdb-testsuite-yet-another-attempt-to-fix-gdb.threads.patch of Package gdb

From 6256bcf098ccf5737dbb8e379d2c0251647aec43 Mon Sep 17 00:00:00 2001
From: Tom de Vries <tdevries@suse.de>
Date: Wed, 22 Oct 2025 08:46:06 +0200
Subject: [PATCH] [gdb/testsuite] Yet another attempt to fix
 gdb.threads/thread-specific-bp.exp

When running test-case gdb.threads/thread-specific-bp.exp using taskset to
select an Efficient-core in a loop, it fails 19 out of 100 runs.

For example, like this:
...
(gdb) continue -a^M
Continuing.^M
^M
Thread 1 "thread-specific" hit Breakpoint 4, end () at thread-specific-bp.c:29^M
29      }^M
(gdb) FAIL: $exp: non_stop=on: continue to end
[Thread 0x7ffff7cbe6c0 (LWP 2348848) exited]^M
Thread-specific breakpoint 3 deleted - thread 2 no longer in the thread list.^M
...

The way we're trying to match this gdb output is:
...
    gdb_test_multiple "$cmd" "continue to end" {
	-re "$\r\n${gdb_prompt} .*${msg_re}\r\n" {
	    pass $gdb_test_name
	}
	-re "\r\n${msg_re}\r\n.*$gdb_prompt " {
	    pass $gdb_test_name
 	}
     }
...

The problem is that the two -re clauses above do not match the output ending
in a prompt, so the default fail in gdb_test_multiple triggers.

Fix this by splitting this up in two gdb_test_multiple calls:
- the first matches a prompt (with or without preceding $msg_re), making sure
  that the default fail doesn't trigger, and
- the second matches $msg_re, if that was not already matched by the first call.

Using this approach, the test-case passes 100 out of 100 runs.

Tested on x86_64-linux, also with make-check-all.sh.

PR testsuite/32688
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=32688
---
 .../gdb.threads/thread-specific-bp.exp          | 17 +++++++++++++----
 1 file changed, 13 insertions(+), 4 deletions(-)

diff --git a/gdb/testsuite/gdb.threads/thread-specific-bp.exp b/gdb/testsuite/gdb.threads/thread-specific-bp.exp
index e7641d2c9b4..dc7a8fbfa76 100644
--- a/gdb/testsuite/gdb.threads/thread-specific-bp.exp
+++ b/gdb/testsuite/gdb.threads/thread-specific-bp.exp
@@ -95,12 +95,21 @@ proc check_thread_specific_breakpoint {non_stop} {
 		  "-" \
 		  "thread 2 no longer in the thread list\\."]]
 
-    gdb_test_multiple "$cmd" "continue to end" {
-	-re "$\r\n${gdb_prompt} .*${msg_re}\r\n" {
+    set test "continue to end"
+    set try_again 0
+    gdb_test_multiple $cmd $test -no-prompt-anchor {
+	-re -wrap "\r\n${msg_re}(?=\r\n).*" {
 	    pass $gdb_test_name
 	}
-	-re "\r\n${msg_re}\r\n.*$gdb_prompt " {
-	    pass $gdb_test_name
+	-re -wrap "" {
+	    set try_again 1
+	}
+    }
+    if { $try_again } {
+	gdb_test_multiple "" $test {
+	    -re "\r\n${msg_re}(?=\r\n)" {
+		pass $gdb_test_name
+	    }
 	}
     }
 

base-commit: 77f7bf5700b2b9be1172c7b5d05d03ee025c5d2c
-- 
2.51.0