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From: Andreas Schwab <schwab@suse.de>
To: Yao Qi <qiyaoltc@gmail.com>
Cc: Zhang Zhen <zhenzhang.zhang@huawei.com>,  <gdb@sourceware.org>,  <xuhanbing@huawei.com>
Subject: Re: The return address of strtok is out of bounds in gdb
References: <5507E977.2030003@huawei.com> <86k2yfg9yi.fsf@gmail.com>
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Date: Tue, 17 Mar 2015 11:26:00 -0000
In-Reply-To: <86k2yfg9yi.fsf@gmail.com> (Yao Qi's message of "Tue, 17 Mar 2015	11:05:57 +0000")
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Yao Qi <qiyaoltc@gmail.com> writes:

> In your case, I suspect GDB prepares the incorrect arguments for
> function strtok due to lack of debugging information, so you'll see
> the error.

Probably just the unknown return type, which defaults to int, so you get
truncation to 32 bits.

> You can get your libc debug info installed, or wrap up strktok like
> this in your program,
>
> char *
> my_strtok(char *str, const char *delim)
> {
>   return strtok (str, delim);
> }
>
> and in gdb,
>
> (gdb) p p1 = my_strtok(a0, se)

Or add a cast to the expected type:

(gdb) p p1 = ((char *(*)())strtok)(a0, se)

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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