3 files changed, 4 insertions, 1 deletions

diff --git a/arch/um/os-Linux/aio.c b/arch/um/os-Linux/aio.c
index 298d5632128b..f6e64026f995 100644
--- a/arch/um/os-Linux/aio.c
+++ b/arch/um/os-Linux/aio.c
@@ -144,6 +144,7 @@ static int aio_thread(void *arg)
                                "errno = %d\n", errno);
                 }
                 else {
+                        /* This is safe as we've just a pointer here. */
                         aio = (struct aio_context *) (long) event.data;
                         if(update_aio(aio, event.res)){
                                 do_aio(ctx, aio);
diff --git a/arch/um/os-Linux/elf_aux.c b/arch/um/os-Linux/elf_aux.c
index e770cb029578..ab33cb3c74ec 100644
--- a/arch/um/os-Linux/elf_aux.c
+++ b/arch/um/os-Linux/elf_aux.c
@@ -14,7 +14,8 @@
 #include "mem_user.h"
 #include <kernel-offsets.h>
 
-#if HOST_ELF_CLASS == ELFCLASS32
+/* Use the one from the kernel - the host may miss it, if having old headers. */
+#if UM_ELF_CLASS == UM_ELFCLASS32
 typedef Elf32_auxv_t elf_auxv_t;
 #else
 typedef Elf64_auxv_t elf_auxv_t;
diff --git a/arch/um/os-Linux/process.c b/arch/um/os-Linux/process.c
index d32413e4b4ce..d9c52387c4a1 100644
--- a/arch/um/os-Linux/process.c
+++ b/arch/um/os-Linux/process.c
@@ -3,6 +3,7 @@
  * Licensed under the GPL
  */
 
+#include <unistd.h>
 #include <stdio.h>
 #include <errno.h>
 #include <signal.h>