Some applications are easier without a GC. Embedded work comes to mind. Realtime guarantees for systems with GC are also somewhat tricky (though not impossible to achieve).
True, but just because a systems language has a GC doesn't mean one has to use it everywhere, it is the only mechanism to allocate memory or that it has to run all the time.
Modula-3 is a good example of how to support all scenarios required by a systems programming language with GC, unfortunately Compaq buying DEC followed by HP buying Compaq, killed all the work the SRC group was doing.
For embedded work check the Oberon compilers sold by Astrobe for ARM Cortex-M3, Cortex-M4 and Cortex-M7, as well as, Xilinx FPGA Systems.
