Re: [PATCH] gdb: use gdb_test_multiple in gdb_breakpoint

[Lancelot SIX <lsix@lancelotsix.com>]

Hi Simon,

On Tue, Jan 03, 2023 at 02:22:16PM -0500, Simon Marchi via Gdb-patches wrote:
> When running the testsuite in a non-optimized build on a slow machine, I
> sometimes get:
> 
>     UNTESTED: gdb.gdb/selftest.exp: Cannot set breakpoint at captured_main, skipping testcase.
> 
> do_self_tests, in lib/selftest-support.exp, uses `with_timeout_factor
> 10`, to account for the fact that reading the debug info of the gdb
> binary (especially in a non-optimized GDB) can take time.  But then it
> ends up calling gdb_breakpoint, which uses gdb_expect with a hard-coded
> timeout of 30 seconds.
> 
> Fix this by making gdb_breakpoint use gdb_test_multiple, which is a
> desired change anyway for this kind of simple command / expected
> output case.
> 
> Change-Id: I9b06ce991cc584810d8cc231b2b4893980b8be75
> ---
>  gdb/testsuite/lib/gdb.exp | 32 +-------------------------------
>  1 file changed, 1 insertion(+), 31 deletions(-)
> 
> diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
> index 135ace68d5ed..5a0cd46d8998 100644
> --- a/gdb/testsuite/lib/gdb.exp
> +++ b/gdb/testsuite/lib/gdb.exp
> @@ -641,9 +641,8 @@ proc gdb_breakpoint { linespec args } {
>  
>      set test_name "gdb_breakpoint: set breakpoint at $linespec"

Should you use $test_name as second arg of the call to gdb_test_multiple
you introduce?  This way the error cases handled by gdb_test_multiple
will the desired test name.

Also, I guess that to make is slightly more consistent with other usages
of gdb_test_multiple, $gdb_test_name should be used instead of
$test_name in the untouched actions.

Best,
Lancelot.

>  
> -    send_gdb "$break_command $linespec\n"
>      # The first two regexps are what we get with -g, the third is without -g.
> -    gdb_expect 30 {
> +    gdb_test_multiple "$break_command $linespec" "" {
>  	-re "$break_message \[0-9\]* at .*: file .*, line $decimal.\r\n$gdb_prompt $" {}
>  	-re "$break_message \[0-9\]*: file .*, line $decimal.\r\n$gdb_prompt $" {}
>  	-re "$break_message \[0-9\]* at .*$gdb_prompt $" {}
> @@ -659,35 +658,6 @@ proc gdb_breakpoint { linespec args } {
>  		send_gdb "$pending_response\n"
>  		exp_continue
>  	}
> -	-re "A problem internal to GDB has been detected" {
> -		if { $print_fail } {
> -		    fail "$test_name (GDB internal error)"
> -		}
> -		gdb_internal_error_resync
> -		return 0
> -	}
> -	-re "$gdb_prompt $" {
> -		if { $print_fail } {
> -			fail $test_name
> -		}
> -		return 0
> -	}
> -	eof {
> -		perror "GDB process no longer exists"
> -		global gdb_spawn_id
> -		set wait_status [wait -i $gdb_spawn_id]
> -		verbose -log "GDB process exited with wait status $wait_status"
> -		if { $print_fail } {
> -			fail "$test_name (eof)"
> -		}
> -		return 0
> -	}
> -	timeout {
> -		if { $print_fail } {
> -			fail "$test_name (timeout)"
> -		}
> -		return 0
> -	}
>      }
>      if { $print_pass } {
>  	pass $test_name
> 
> base-commit: a7d5fcaf8e15820f997ba7774a8eef7ab7e2f2e3
> -- 
> 2.39.0
>