diff --git a/gc.h b/gc.h
index 7c7f0efd1b..cf794fa514 100644
--- a/gc.h
+++ b/gc.h
@@ -6,6 +6,8 @@
 #define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("movq\t%%rsp, %0" : "=r" (*(p)))
 #elif defined(__i386) && defined(__GNUC__)
 #define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("movl\t%%esp, %0" : "=r" (*(p)))
+#elif defined(__powerpc64__) && defined(__GNUC__)
+#define SET_MACHINE_STACK_END(p) __asm__ __volatile__ ("mr\t%0, %%r1" : "=r" (*(p)))
 #else
 NOINLINE(void rb_gc_set_stack_end(VALUE **stack_end_p));
 #define SET_MACHINE_STACK_END(p) rb_gc_set_stack_end(p)