Re: [PATCH 1/2] gdb/testsuite: fix gdb.threads/threadcrash.exp on 32-bit arm targets

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

On 2/1/24 16:58, Guinevere Larsen wrote:
> There are 2 issues with the test gdb.threads/threadcrash.exp on arm
> targets, both relating to issues in how the targets handles gcores. The
> first is that the test fails to cout the number of threads in the
> inferior and the second is that GDB can't properly backtrace from a
> gcore.
> 
> The first error is fixed on this commit by getting the convenience
> variable _inferior_thread_count as opposed to calculating it based on
> the output of "info threads"
> 
> For the second, this test just emits a single xfail referring back to PR
> corefiles/31294, which tracks the issues with gcores in 32-bit arm
> targets.
> 

Hi Guinevere,

the fact that the PR has the corefiles component suggests that there's a 
problem with gdb, which means a kfail should be used. An xfail is used 
to indicate problems in the environment (meaning external to gdb), like 
a known problem in the linux kernel, or incorrect debug info generated 
by the compiler, etc.

Thanks,
- Tom

> Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31294
> ---
>   gdb/testsuite/gdb.threads/threadcrash.exp | 15 ++++++++-------
>   1 file changed, 8 insertions(+), 7 deletions(-)
> 
> diff --git a/gdb/testsuite/gdb.threads/threadcrash.exp b/gdb/testsuite/gdb.threads/threadcrash.exp
> index d3e3494cbea..362c4c5879d 100644
> --- a/gdb/testsuite/gdb.threads/threadcrash.exp
> +++ b/gdb/testsuite/gdb.threads/threadcrash.exp
> @@ -27,12 +27,9 @@
>   proc test_thread_count {} {
>       set thread_count 0
>   
> -    gdb_test_multiple "info threads" "getting thread count" -lbl {
> -	-re "\(Thread\|LWP\)" {
> -	    incr thread_count
> -	    exp_continue
> -	}
> -	-re "$::gdb_prompt " {
> +    gdb_test_multiple "print \$_inferior_thread_count" "getting thread count" {
> +	-re ".* = (\[0-9]+).*" {
> +	    set thread_count $expect_out(1,string)
>   	    gdb_assert {$thread_count == 7}
>   	}
>       }
> @@ -230,4 +227,8 @@ test_live_inferior
>   
>   test_corefile
>   
> -test_gcore
> +if { [is_aarch32_target] } {
> +    xfail "gcore tests fail on 32-bit arm, see PR corefiles/31294"
> +} else {
> +    test_gcore
> +}