> Looks ok. I wonder if you want to explicitely document that max_size < size
> doesn't have any effect on actual code generation and is not checked for.
Documentation amended to that effect:
-- Built-in Function: void *__builtin_alloca_with_align_and_max
(size_t size, size_t alignment, size_t max_size)
Similar to `__builtin_alloca_with_align' but takes an extra
argument specifying an upper bound for SIZE in case its value
cannot be computed at compile time, for use by `-fstack-usage',
`-Wstack-usage' and `-Walloca-larger-than' computations. MAX_SIZE
has no effect on code generation and no attempt is made to check
its compatibility with SIZE.
> Also it seems that __builtin_alloca_with_align (20, 8, 16) will still
> account 20 as the size and not 16 compared to 20 arriving in a variable
> which is when 16 will be used. So at least for accounting always use MIN
> (size, max_size)?
The implementation is in keeping with the above documentation, i.e. SIZE will
prevail if its value can be computed at compile time.
--
Eric Botcazou
