diff --git a/include/common/debug.h b/include/common/debug.h
index 3c99ce5..4c5560f 100644
--- a/include/common/debug.h
+++ b/include/common/debug.h
@@ -4,8 +4,8 @@
  * SPDX-License-Identifier: BSD-3-Clause
  */
 
-#ifndef __DEBUG_H__
-#define __DEBUG_H__
+#ifndef DEBUG_H
+#define DEBUG_H
 
 /*
  * The log output macros print output to the console. These macros produce
@@ -90,11 +90,7 @@
 void __dead2 __stack_chk_fail(void);
 
 void tf_log(const char *fmt, ...) __printflike(1, 2);
-int tf_printf(const char *fmt, ...) __printflike(1, 2);
-int tf_snprintf(char *s, size_t n, const char *fmt, ...) __printflike(3, 4);
-int tf_vprintf(const char *fmt, va_list args);
-int tf_string_print(const char *str);
 void tf_log_set_max_level(unsigned int log_level);
 
 #endif /* __ASSEMBLY__ */
-#endif /* __DEBUG_H__ */
+#endif /* DEBUG_H */
diff --git a/include/lib/libc/stdio.h b/include/lib/libc/stdio.h
index 83fd18c..3d9323e 100644
--- a/include/lib/libc/stdio.h
+++ b/include/lib/libc/stdio.h
@@ -11,6 +11,7 @@
 #ifndef STDIO_H
 #define STDIO_H
 
+#include <cdefs.h>
 #include <stdio_.h>
 
 #ifndef NULL
@@ -19,14 +20,11 @@
 
 #define EOF            -1
 
-int printf(const char *fmt, ...);
-int snprintf(char *s, size_t n, const char *fmt, ...);
-int sprintf(char *s, const char *fmt, ...);
-int sscanf(const char *s, const char *fmt, ...);
+int printf(const char *fmt, ...) __printflike(1, 2);
+int snprintf(char *s, size_t n, const char *fmt, ...) __printflike(3, 4);
 
 #ifdef STDARG_H
-int vsnprintf(char *s, size_t n, const char *fmt, va_list arg);
-int vsprintf(char *s, const char *fmt, va_list arg);
+int vprintf(const char *fmt, va_list args);
 #endif
 
 int putchar(int c);