Hello, Please check Dynamic C 9.62 user's manual at the below link in the page number 206.
"If you are using Dynamic C 9.30 or later, the _RK_FIXED_VECTORS macro must be used to conditionally
compile code containing the interrupt_vector keyword. For Rabbit 3000A and later CPUs,
Dynamic C makes use of the new RAMSR capability to make in-RAM interrupt table access fast. The following
code demonstrates the correct way to use _RK_FIXED_VECTORS so as to eliminate errors
regarding undefined interrupt vectors"