Backuss naur form grammar variable declaration in c

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Homework Statement

Write a grammar that recognize a C variable declaration made up only of legal combinations of the following keywords: int char float double signed unsigned long short volatile const
and a variable name.
The grammar should be able to accepts all such legal declarations for example:
volatile unsigned int a; ...
but :
volatile signed unsigned int a;
should not be accepted.

Homework Equations

declaration ::= variable

The Attempt at a Solution

1. declarations ::= variable ; declaration
2. variable ::= keyword name
3. keyword ::= type
4. type ::= type-int | type-char | float | double
5. type-int ::= int type-l type-sign
6. type-char ::= char type-sign
7. type-sign ::= signed | unsigned | empty
8. type-l ::= long | short | empty

I think that my solution is not correct.

 

[MisterX]

5. type-int ::= int type-l type-sign

Wouldn't this allow declarations such as int unsigned, when it should be allowing declarations such as unsigned int? In addition you don't seem to have any items for the volatile and const specifiers.

Also, the "int" may be unnecessary in some declarations. The following declarations should be allowed:

short a;
unsigned short b;
signed short c;
long d;
unsigned long e;
signed long f;
signed g; //same as signed int
unsigned h; //same as unsigned int

Additionally these are allowed by more recent versions of the C standard:

long long i;
unsigned long long j;
signed long long k;