Polyspace compile error for "_Bool" type name by using diab compiler

We have a self-defined type named "_Bool", as below:

typedef unsigned char uint8_t;
typedef uint8_t _Bool;

When we do the Code prover analysis of the C file, it popup error:

We know the C99 standard using "_Bool" as default boolean type, but we check the "C90 standard", still not work!

It not happened when we select other compilers!