Re: [PATCH RESEND 0/2] RISC-V: Handle the siginfo_t offset problem

From: Andreas Schwab
Date: Thu Jul 04 2019 - 03:20:30 EST


On Jul 03 2019, Alistair Francis <alistair23@xxxxxxxxx> wrote:

> On Wed, Jul 3, 2019 at 12:08 AM Andreas Schwab <schwab@xxxxxxx> wrote:
>>
>> On Jul 02 2019, Alistair Francis <alistair.francis@xxxxxxx> wrote:
>>
>> > In the RISC-V 32-bit glibc port [1] the siginfo_t struct in the kernel
>> > doesn't line up with the struct in glibc. In glibc world the _sifields
>> > union is 8 byte alligned (although I can't figure out why)
>>
>> Try ptype/o in gdb.
>
> That's a useful tip, I'll be sure to use that next time.

It was a serious note. If the structs don't line up then there is a
mismatch in types that cannot be solved by adding spurious padding. You
need to fix the types instead.

Andreas.

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Andreas Schwab, SUSE Labs, schwab@xxxxxxx
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