diff --git a/include/io_storage.h b/include/io_storage.h
index 71f5d26..f67e5d0 100644
--- a/include/io_storage.h
+++ b/include/io_storage.h
@@ -31,6 +31,8 @@
 #ifndef __IO_H__
 #define __IO_H__
 
+#ifndef __ASSEMBLY__
+
 #include <stdint.h>
 #include <stdio.h>	/* For ssize_t */
 
@@ -125,4 +127,5 @@
 int io_close(io_handle handle);
 
 
+#endif /* __ASSEMBLY__ */
 #endif /* __IO_H__ */
diff --git a/include/semihosting.h b/include/semihosting.h
index d70fcba..0244cad 100644
--- a/include/semihosting.h
+++ b/include/semihosting.h
@@ -61,7 +61,7 @@
 int semihosting_file_open(const char *file_name, unsigned int mode);
 int semihosting_file_seek(int file_handle, unsigned int offset);
 int semihosting_file_read(int file_handle, int *length, void *buffer);
-int semihosting_file_write(int file_handle, int *length, void *buffer);
+int semihosting_file_write(int file_handle, int *length, const void *buffer);
 int semihosting_file_close(int file_handle);
 int semihosting_file_length(int file_handle);
 int semihosting_system(char *command_line);