This line:
[quote user="gongy shen"]-u _Reset /* Force load of reset interrupt handler */[/quote]
tells the linker that it must satisfy the symbol "_Reset", which is found only in the RTS library's vectors section.
Somewhere else in the program, you must be referring to one of the symbols in the CSL library's vectors section, specifically "RST" or "_VECSTART". I recommend you edit the linker command file to remove the option "-u _Reset" and let the linker choose the CSL's vectors section.