[PATCH] Fix EQ_ATTR_ALT size calculation (PR bootstrap/87417)

[Jeff Law]

On 9/24/18 11:15 PM, Richard Sandiford wrote:
> Ilya Leoshkevich <iii@linux.ibm.com> writes:
>> Bootstrap and regtest running on s390x-redhat-linux.
>>
>> "r264537: Change EQ_ATTR_ALT to support up to 64 alternatives" changed
>> the format of EQ_ATTR_ALT from ii to ww.  This broke the bootstrap on
>> 32-bit systems, because the formula for rtx_code_size assumed that only
>> certain codes contain HOST_WIDE_INTs.  This did not surface on 64-bit
>> systems, because rtunion is 8 bytes anyway, but on 32-bit systems it's
>> only 4 bytes.  This resulted in out-of-bounds writes and memory
>> corruptions in genattrtab.
>>
>> gcc/ChangeLog:
>>
>> 2018-09-24  Ilya Leoshkevich  <iii@linux.ibm.com>
>>
>> 	PR bootstrap/87417
>> 	* rtl.c (rtx_code_size): Take into account that EQ_ATTR_ALT
>> 	contains HOST_WIDE_INTs when computing its size.
> 
> OK.  Thanks for the quick fix.
And I'll note that my testers were picking up this failure on various
targets -- they're all happy now.

jeff