> On Oct 5, 2021, at 1:30 PM, Jason Merrill <ja...@redhat.com> wrote:
>
>>> 'decl_had_value_expr_p' and check && !decl_had_value_expr_p here?
>>> So sth like
>> I can do this -:) I agree that the change will make the code simpler.
>> However, my major concern with this change is: later when people look at
>> this change, they might ask:
>> Why we should not initialize a variable with VALUE_EXPR? And whether the
>> variable whose VALUE_EXPR
>> was created by “gimplify_vla_decl” should be excluded?
>> My new function and comments were all for this purpose.
>> If I go with this change, at least we should add some comments to explain
>> this as following, what do you think?
>>>
>>> diff --git a/gcc/gimplify.c b/gcc/gimplify.c
>>> index b27776af7c8..9013f385f13 100644
>>> --- a/gcc/gimplify.c
>>> +++ b/gcc/gimplify.c
>>> @@ -1872,6 +1872,7 @@ gimplify_decl_expr (tree *stmt_p, gimple_seq *seq_p)
>>> {
>>> tree init = DECL_INITIAL (decl);
>>> bool is_vla = false;
>> + /* Check whether a decl has FE created VALUE_EXPR here BEFORE
>> + gimplify_vla_decl creates VALUE_EXPR for vla decl. */
>>> + bool decl_had_value_expr_p = DECL_HAS_VALUE_EXPR_P (decl);
>>>
>>> poly_uint64 size;
>>> if (!poly_int_tree_p (DECL_SIZE_UNIT (decl), &size)
>>> @@ -1934,7 +1935,8 @@ gimplify_decl_expr (tree *stmt_p, gimple_seq *seq_p)
>>> /* When there is no explicit initializer, if the user requested,
>>> We should insert an artifical initializer for this automatic
>>> variable. */
>>> - else if (is_var_need_auto_init (decl))
>>> + else if (is_var_need_auto_init (decl)
>> + /* If the VAR_DECL has DECL_VALUE_EXPR that was created by FE (usually
>> C++FE),
>> + it's a proxy varaible, and FE already initializd the DECL_VALUE_EXPR of
>> it. */
>
> I'd suggest merging this comment into the comment on the variable declaration.
Okay, will merge these two comments into one and put it on the variable
declaration.
thanks.
Qing
