Re: RFA: PR 68770: Fix use of uninitialised value in secondary_reload

[Jeff Law <law at redhat dot com>]

On 12/22/2015 03:04 AM, Nick Clifton wrote:
> Hi Guys,
>
>    The patch below fixes PR 68770 - a warning from valgrind about an
>    uninitialised value being used in the default_secondary_reload.  The
>    problem turns out to the in copy_costs which creates its own secondary
>    reload information structure, but it does not initialise all of the
>    fields.  One field in particular - t_icode - is examined by
>    default_secondary_reload, and it was this that was triggering the
>    valgrind warning.
>
>    Tested with no regressions on a x86_64-pc-linux-gnu and a
>    powerpc64-le-linux-gnu toolchain.
>
>    OK to apply ?
>
> Cheers
>    Nick
>
> gcc/ChangeLog
> 2015-12-22  Nick Clifton  <nickc@redhat.com>
>
> 	PR target/68770
> 	* ira-costs.c (copy_cost): Initialise the t_code field of the sri
> 	structure.
Can you please reduce the testcase from the BZ so that it can be 
included in the testsuite?  I realize it might take a long time with 
multidelta because of the need to run the compiler with valgrind.  But 
once you've got the right script, you ought to be able to just let it 
run overnight or whatever.

To speed things up, you might consider first trying to compile the case 
without valgrind and if that fails, then that particular reduction is 
"not interesting".  That should dramatically cut down on the number of 
times you have to run the compiler under valgrind control.

With a testcase, this is fine.
jeff