ex_reg 410 gc/mark.c EXCEPTION_REGISTRATION ex_reg; ex_reg 472 gc/mark.c er.ex_reg.handler = mark_ex_handler; ex_reg 473 gc/mark.c asm volatile ("movl %%fs:0, %0" : "=r" (er.ex_reg.prev)); ex_reg 519 gc/mark.c asm volatile ("mov %0, %%fs:0" : : "r" (er.ex_reg.prev));