[PATCH] uml: compile fixes for gcc 4

This is a bunch of compile fixes provoked by building UML with gcc 4.  There
are a bunch of signedness mismatches, a couple of uninitialized references,
and a botched C99 structure initialization which had somehow gone unnoticed.

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/um/os-Linux/file.c b/arch/um/os-Linux/file.c
index 77d4066..fd45bb2 100644
--- a/arch/um/os-Linux/file.c
+++ b/arch/um/os-Linux/file.c
@@ -363,7 +363,7 @@
 		       (int (*)(int, void *, int)) write, copy_to_user_proc));
 }
 
-int os_file_size(char *file, long long *size_out)
+int os_file_size(char *file, unsigned long long *size_out)
 {
 	struct uml_stat buf;
 	int err;