diff --git a/lib/csu/riscv/crt1_c.c b/lib/csu/riscv/crt1_c.c
--- a/lib/csu/riscv/crt1_c.c
+++ b/lib/csu/riscv/crt1_c.c
@@ -63,6 +63,7 @@
 _start(void *procargs, const struct Obj_Entry *obj, void (*cleanup)(void))
 {
 	__asm__(
+	    ".cfi_undefined ra\n"
 	    ".option push\n"
 	    ".option norelax\n"
 	    /* Safe before call - lla will not clobber any other registers. */