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More Const than Const

It just so happened that I read about the syntax of the programming language C here. And somehow it occurred to me that some of the rules allow for quite nonsensical expressions. Take for example the following simple code snippet:

int main(int argc, char* argv[]){
    int * const a;
    return 0;
}

This is perfectly valid code and it makes sense, if you want to make sure the compiler knows that this pointer itself is constant. According to the syntactic rules however you are not restricted on the number of const quialifiers you put there, so the following is also perfectly valid C code:

int main(int argc, char* argv[]){
    int * const const const const const const const const a;
    return 0;
}

Just in case you want to make sure the compiler really does not miss that a is a constant pointer. GCC actually compiles this code just fine, but you will get warnings if you add the -Wall flag for stricter code checking.