Re: [PATCH][RFC] Prevent TYPE_PRECISION on VECTOR_TYPEs

[Jeff Law <jeffreyalaw@gmail.com>]

On 6/23/23 02:26, Richard Biener via Gcc-patches wrote:
> The following makes sure that using TYPE_PRECISION on VECTOR_TYPE
> ICEs when tree checking is enabled.  This should avoid wrong-code
> in cases like PR110182 and instead ICE.
> 
> It also introduces a TYPE_PRECISION_RAW accessor and adjusts
> places I found that are eligible to use that.
> 
> This patch requires (at least) the series of patches I will
> followup this with.  I have to re-bootstrap / test to look
> for further fallout (I've picked this up again after some weeks).
> 
> Opinions?
> 
> Thanks,
> Richard.
> 
> 	* tree.h (TYPE_PRECISION): Check for non-VECTOR_TYPE.
> 	(TYPE_PRECISION_RAW): Provide raw access to the precision
> 	field.
> 	* tree.cc (verify_type_variant): Compare TYPE_PRECISION_RAW.
> 	(gimple_canonical_types_compatible_p): Likewise.
> 	* tree-streamer-out.cc (pack_ts_type_common_value_fields):
> 	Stream TYPE_PRECISION_RAW.
> 	* tree-streamer-in.cc (unpack_ts_type_common_value_fields):
> 	Likewise.
> 	* lto-streamer-out.cc (hash_tree): Hash TYPE_PRECISION_RAW.
Given how easy it is to incorrectly use TYPE_PRECISION on VECTOR_TYPE, 
I'm all for it.

jeff