Is the compiler limited in any way?
What are the recommended compilers for the S32K148?
S32DS does not introduce any limitation to GCC build tools.
There are several alternatives to GCC compiler for S32K MCUs- e.g. Keil/ARM, IAR, GreenHills....
FYI: you can use GHS and IAR eclipse plugin and integrate them into S32 Design Studio.
Hope it helps.