Index: uspace/lib/c/include/io/klog.h
===================================================================
--- uspace/lib/c/include/io/klog.h	(revision 74fec95157755e9eb38e0effb7f2c4cdabcfd4cb)
+++ uspace/lib/c/include/io/klog.h	(revision e522da4109b40388dff4586765ec8531c5d650a5)
@@ -38,8 +38,10 @@
 #include <sys/types.h>
 #include <stdarg.h>
+#include <io/verify.h>
 
 extern size_t klog_write(const void *, size_t);
 extern void klog_update(void);
-extern int klog_printf(const char *, ...);
+extern int klog_printf(const char *, ...)
+    PRINTF_ATTRIBUTE(1, 2);
 extern int klog_vprintf(const char *, va_list);
 
Index: uspace/lib/c/include/io/log.h
===================================================================
--- uspace/lib/c/include/io/log.h	(revision 74fec95157755e9eb38e0effb7f2c4cdabcfd4cb)
+++ uspace/lib/c/include/io/log.h	(revision e522da4109b40388dff4586765ec8531c5d650a5)
@@ -36,4 +36,5 @@
 
 #include <stdarg.h>
+#include <io/verify.h>
 
 typedef enum {
@@ -44,5 +45,5 @@
 	LVL_DEBUG,
 	LVL_DEBUG2,
-
+	
 	/** For checking range of values */
 	LVL_LIMIT
@@ -50,5 +51,6 @@
 
 extern int log_init(const char *, log_level_t);
-extern void log_msg(log_level_t, const char *, ...);
+extern void log_msg(log_level_t, const char *, ...)
+    PRINTF_ATTRIBUTE(2, 3);
 extern void log_msgv(log_level_t, const char *, va_list);
 
Index: uspace/lib/c/include/io/verify.h
===================================================================
--- uspace/lib/c/include/io/verify.h	(revision e522da4109b40388dff4586765ec8531c5d650a5)
+++ uspace/lib/c/include/io/verify.h	(revision e522da4109b40388dff4586765ec8531c5d650a5)
@@ -0,0 +1,52 @@
+/*
+ * Copyright (c) 2012 Martin Decky
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** @addtogroup libc
+ * @{
+ */
+/** @file
+ */
+
+#ifndef LIBC_IO_VERIFY_H_
+#define LIBC_IO_VERIFY_H_
+
+#ifndef NVERIFY_PRINTF
+
+#define PRINTF_ATTRIBUTE(start, end) \
+	__attribute__((format(gnu_printf, start, end)))
+
+#else /* NVERIFY_PRINTF */
+
+#define PRINTF_ATTRIBUTE(start, end)
+
+#endif /* NVERIFY_PRINTF */
+
+#endif
+
+/** @}
+ */
Index: uspace/lib/c/include/stdio.h
===================================================================
--- uspace/lib/c/include/stdio.h	(revision 74fec95157755e9eb38e0effb7f2c4cdabcfd4cb)
+++ uspace/lib/c/include/stdio.h	(revision e522da4109b40388dff4586765ec8531c5d650a5)
@@ -39,15 +39,5 @@
 #include <stdarg.h>
 #include <str.h>
-
-#ifndef NVERIFY_PRINTF
-
-#define PRINTF_ATTRIBUTE(start, end) \
-	__attribute__((format(gnu_printf, start, end)))
-
-#else /* NVERIFY_PRINTF */
-
-#define PRINTF_ATTRIBUTE(start, end)
-
-#endif /* NVERIFY_PRINTF */
+#include <io/verify.h>
 
 #define EOF  (-1)