gcc-plugin/src/c-expr.y: fixed reduce/reduce conflicts.

gcc-plugin/src/c-expr.y

@@ -184,15 +184,15 @@ sequence: expression {
       }
 ;
 
-expression: identifier | binary_expression | unary_expression;
+expression: binary_expression
+;
 
 /* XXX: `ensure_bound' below leads to errors raised even for non-significant
    arguments---e.g., junk after pragma.  */
 identifier: YCPP_NAME  { $$ = ensure_bound (loc, $1); }
 ;
 
-binary_expression: multiplicative_expression
-     | additive_expression
+binary_expression: additive_expression
 ;
 
 multiplicative_expression: multiplicative_expression YCPP_MULT cast_expression {
@@ -217,9 +217,7 @@ cast_expression: unary_expression
 		 /* XXX: No support for '(' TYPE-NAME ')' UNARY-EXPRESSION.  */
 ;
 
-unary_expression:
-       primary_expression
-     | postfix_expression
+unary_expression: postfix_expression
      | YCPP_AND cast_expression {
        $$ = build_addr (ensure_bound (loc, $2), current_function_decl);
      }