... snip ...
Then you should know better. I suspect you are largely ignored.
All of which can hold values between 32767 and -32767 as he said.
unsigned ints are not ints. They are a different type and follow different rules, such as the use of modulo arithmetic. Which doesn't affect the statement about ints.
Then it isn't a C compiler, by definition. It may still be useful. The point of a standard is to allow confidence that source code will work on any system that is standards compliant. Use of extensions should be limited to clearly identified modules.