[PATCH v4 6/6] gdb/testsuite: Add kfail in gdb.threads/threadcrash.exp on 32-bit arm targets

[Tom de Vries <tdevries@suse.de>]

There is an issue with the test gdb.threads/threadcrash.exp on arm
targets, relating to how the targets handles gcores.  The issue is that GDB
can't properly backtrace from a gcore.

Add a kfail referring back to PR corefiles/31294, which tracks the issues with
gcores in 32-bit arm targets.

I cannot reproduce the problem, so this is a best effort based on the logs in
the PR.

Tested on arm-linux and x86_64-linux.

Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31294
---
 gdb/testsuite/gdb.threads/threadcrash.exp | 27 +++++++++++++++--------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/gdb/testsuite/gdb.threads/threadcrash.exp b/gdb/testsuite/gdb.threads/threadcrash.exp
index c72ce73fd6d..7839f5c358e 100644
--- a/gdb/testsuite/gdb.threads/threadcrash.exp
+++ b/gdb/testsuite/gdb.threads/threadcrash.exp
@@ -94,14 +94,14 @@ proc thread_apply_all {} {
 	}
     }
 
-    gdb_assert {$unwind_fail == false}
-
     if { $have_sleep == -1 } {
 	set have_sleep 0
     }
     if { $have_pthread_kill == -1 } {
 	set have_pthread_kill 0
     }
+
+    return [expr !$unwind_fail]
 }
 
 # Perform all the tests we're interested in.  They are:
@@ -109,16 +109,25 @@ proc thread_apply_all {} {
 # * Creating the list of backtraces for all threads seen
 # * testing if GDB recreated the full backtrace we expect for all threads
 
-proc do_full_test {} {
+proc do_full_test { phase } {
     global have_sleep
     global have_pthread_kill
     global test_list
     set thread_count [get_valueof "" "\$_inferior_thread_count" 0]
     gdb_assert {$thread_count == 7}
 
-    thread_apply_all
-
-    gdb_assert {$thread_count == [llength $test_list]}
+    set test thread_apply_all
+    set res [$test]
+    if { $res && $thread_count == [llength $test_list] } {
+	pass $test
+    } else {
+	set have_kfail [expr [string equal $phase gcore] && [is_aarch32_target]]
+	if { $have_kfail } {
+	    kfail $test
+	} else {
+	    fail $test
+	}
+    }
 
     if { $have_sleep } {
 	set sleep ".*sleep.*"
@@ -209,7 +218,7 @@ proc_with_prefix test_live_inferior {} {
     gdb_breakpoint "breakpt"
     gdb_continue_to_breakpoint "running to breakpoint" ".*"
 
-    do_full_test
+    do_full_test live_inferior
 }
 
 # Do all preparation steps for running the corefile tests, then
@@ -229,7 +238,7 @@ proc_with_prefix test_corefile {} {
 	     "A program is being debugged already\\\.  Kill it\\\? \\\(y or n\\\) " \
 	     "y"
 
-    do_full_test
+    do_full_test corefile
 }
 
 # Do all preparation steps for running the gcore tests, then
@@ -267,7 +276,7 @@ proc_with_prefix test_gcore {} {
 	     "A program is being debugged already\\\.  Kill it\\\? \\\(y or n\\\) " \
 	     "y"
 
-    do_full_test
+    do_full_test gcore
 }
 
 standard_testfile
-- 
2.35.3