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

[Luis Machado <lgustavo at codesourcery dot 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