[Bug tree-optimization/102586] [12 Regression] ICE in clear_padding_type, at gimple-fold.c:4798 since r12-3433-ga25e0b5e6ac8a77a

[qing.zhao at oracle dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102586

--- Comment #23 from Qing Zhao <qing.zhao at oracle dot com> ---
> On Feb 11, 2022, at 9:29 AM, jason at gcc dot gnu.org <gcc-bugzilla@gcc.gnu.org> wrote:
> 
> I wonder why -fauto-var-init uses builtin_clear_padding instead of just
> zero-initializing the whole object before normal initialization, as with
> value-initialization?  With a new object we don't need to get clever.

In the initial several versions of the implementation, I didn’t use
builtin_clear_padding, other that
that, I just zero-initialized the whole object before normal initialization.
However, multiple people
suggested to use builtin_clear_padding instead. Then in the later
implementations, I used
builtin_clear_padding for the padding initialization.