Re: [PATCH,v2] Make gdb.arch/i386-biarch-core.exp more robust

[Luis Machado <lgustavo@codesourcery.com>]

On 02/07/2017 04:51 AM, Pedro Alves wrote:
> On 02/07/2017 10:11 AM, Luis Machado wrote:
>> This test attempts to load a x86 core file no matter what target
>> architectures the tested GDB supports. If GDB doesn't know how to handle
>> a i386 target, it is very likely the core file will not be recognized.
>>
>> In this case we should still attempt to load a core file to make sure GDB
>> doesn't crash or throws an internal error.  But we should not proceed to
>> try to read memory unconditionally.
>>
>> This patch makes the test check for proper i386 arch support in GDB and bails
>> out if i386 is not supported and the core file format is not recognized.
>>
>> This addresses the spurious aarch64-elf failures i'm seeing for this test.
>>
>> gdb/testsuite/ChangeLog:
>>
>> YYYY-MM-DD  Luis Machado  <lgustavo@codesourcery.com>
>>
>> 	* gdb.arch/i386-biarch-core.exp: Check for i386 arch support and
>> 	return if core file is not recognized
>> ---
>>  gdb/testsuite/gdb.arch/i386-biarch-core.exp | 30 ++++++++++++++++++++++++++++-
>>  1 file changed, 29 insertions(+), 1 deletion(-)
>>
>> diff --git a/gdb/testsuite/gdb.arch/i386-biarch-core.exp b/gdb/testsuite/gdb.arch/i386-biarch-core.exp
>> index 4c5f450..a05096c 100644
>> --- a/gdb/testsuite/gdb.arch/i386-biarch-core.exp
>> +++ b/gdb/testsuite/gdb.arch/i386-biarch-core.exp
>> @@ -54,6 +54,18 @@ if {$corestat(size) != 102400} {
>>      return -1
>>  }
>>
>> +# First check if this particular GDB supports i386, otherwise we should not
>> +# expect the i386 core file to be loaded successfully.
>> +set supports_arch_i386 1
>> +set test "complete set architecture i386"
>> +gdb_test_multiple $test $test {
>> +    -re ".*\r\nset architecture i386\r\n(.*\r\n)?$gdb_prompt $" {
>
> ".*" at the start of a -re is implicit/redundant.
>

Thanks. Good to know.

>> +    }
>> +    -re "\r\n$gdb_prompt $" {
>> +        set supports_arch_i386 0
>> +    }
>> +}
>> +
>>  # Wrongly built GDB complains by:
>>  # "..." is not a core dump: File format not recognized
>>  # As the provided test core has 64bit PRSTATUS i386 built GDB cannot parse it.
>> @@ -62,7 +74,23 @@ if {$corestat(size) != 102400} {
>>  # objcopy as it corrupts the core file beyond all recognition.
>>  # The output therefore does not matter much, just we should not get GDB
>>  # internal error.
>> -gdb_test "core-file ${corefile}" ".*" "core-file"
>> +#
>> +# If this particular GDB does not support i386, it is expected GDB will not
>> +# recognize the core file.  If it does anyway, it should not crash.
>> +set test "load core file"
>> +gdb_test_multiple "core-file ${corefile}" $test {
>> +    -re ".* no core file handler recognizes format(.*\r\n)?$gdb_prompt $" {
>
> Ditto.  Also, why the "(....)?" in "(.*\r\n)?" ?
>

I think this was from a copy/paste.

>> +	if { $supports_arch_i386 } {
>> +	    fail $test
>> +	} else {
>> +	    untested $test
>
> The "load core file" test was a pass, this "else" outcome is expected.
> What's untested is the next test.  Either write something like:
>
>             pass $test
>             untested ".text is readable (core file unrecognized)"
>             return
>
> or here write only:
>
>             pass $test
>
> and put the untested after the gdb_test_multiple, close to
> the following gdb_test.
>
>> +	    return
>> +	}
>> +    }
>> +    -re "\r\n$gdb_prompt $" {
>> +	pass $test
>> +    }
>> +}
>>

I'll address the above in a new version.

Thanks,
Luis