Re: filling area by color atack safety

Michael S <already5chosen@yahoo.com> writes:

On Tue, 19 Mar 2024 21:40:22 -0700
Tim Rentsch <tr.17687@z991.linuxsc.com> wrote:

Michael S <already5chosen@yahoo.com> writes:

...

Tim Rentsch <tr.17687@z991.linuxsc.com> writes:

...

static  _Bool  change_it( UI w, UI h, Color [w][h], Point, Color,
Color );

Besides, I don't think that use of VLA in library code is a good
idea. VLA is optional in latest C standards.  And incompatible with
C++. 

 
The code uses a variably modified type, not a variable length
array.

>
I am not sufficiently versed in C Standard terminology to see a
difference.

A VLA is a declared object -- an array with a size that is not a
compile-time constant.  A variably modified type is just a type, not an
object.  Obviously one can use such a type to declare a VLA, but when it
is the type of a function parameter, there need be no declared object
with that type.  Usually the associated function argument will have been
dynamically allocated.

Aren't they both introduced in C99 and made optional in later
standards?

I think so but that's a shame since VMTs are very helpful for writing
array code.  They avoid the need to keep calculating the index with
multiplications.

Making both optional was a classic case of throwing the baby out with
the bath water.  Few of the objections raised about VLAs apply to VMTs.

--
Ben.