From: Yao Qi <yao@codesourcery.com>
To: Mark Kettenis <mark.kettenis@xs4all.nl>
Cc: gdb-patches@sourceware.org
Subject: Re: [patch, testsuite] gdb.base/savedregs.exp: SIGSEGV -> SIGILL
Date: Thu, 09 Jun 2011 13:10:00 -0000 [thread overview]
Message-ID: <4DF0C613.70101@codesourcery.com> (raw)
In-Reply-To: <201106091117.p59BHRWi025356@glazunov.sibelius.xs4all.nl>
On 06/09/2011 07:17 PM, Mark Kettenis wrote:
>> Date: Thu, 09 Jun 2011 17:28:09 +0800
>> From: Yao Qi <yao@codesourcery.com>
>>
>> In current gdb.base/savedregs.exp, signal handler is installed for
>> signal SIGSEGV, and SIGSEGV is trigger by `*(char *)0 = 0;'. However,
>> on non-mmu uclinux system, writing to an address 0x0 doesn't trigger
>> SIGSEGV.
>>
>> In my patch, SIGILL is chosen to replace SIGSEGV. One assumption here
>> is that 0xffff is an invalid instruction on all ports.
>
> Please don't do this. You're changing the test significantly. And
I don't think the test is changed *significantly*. The purpose of
writing to zero, at least in this case, is to trigger a signal, and
check the register in signal trampoline frame. Either SIGSEGV or SIGILL
meets this need.
> there is no guarantee that 0xffff is an invalid instruction. Heck
> most platforms don't even have 16-bit instructions.
It is possible to find a `common' invalid instruction over all ports,
even 0xffff may not be.
--
Yao (é½å°§)
next prev parent reply other threads:[~2011-06-09 13:10 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-06-09 9:28 Yao Qi
2011-06-09 10:08 ` Andreas Schwab
2011-06-09 10:53 ` Yao Qi
2011-06-09 11:19 ` Mark Kettenis
2011-06-09 11:41 ` Pedro Alves
2011-06-09 13:25 ` Yao Qi
2011-06-09 13:10 ` Yao Qi [this message]
2011-06-09 14:25 ` Pedro Alves
2011-06-20 4:13 ` [patch V2, testsuite] gdb.base/savedregs.exp: SIGSEGV -> SIGALRM Yao Qi
2011-06-20 7:03 ` Mark Kettenis
2011-06-20 8:26 ` Yao Qi
2011-06-20 11:12 ` Mark Kettenis
2011-06-20 15:07 ` Yao Qi
2011-06-20 15:14 ` Paul Koning
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