diff --git a/float.h b/float.h
index e677f18..b8887ed 100644
--- a/float.h
+++ b/float.h
@@ -1,6 +1,10 @@
 #if !defined(_FLOAT_H) || defined(__LIBC_GUARDLESS_INCLUDE)
+#if !defined(__LIBC_GUARDLESS_INCLUDE)
+#define _FLOAT_H 1
+#endif
 
-#ifndef _FLOAT_H
+#ifndef __FLOAT_H_MACROS
+#define __FLOAT_H_MACROS 1
 
 #define FLT_ROUNDS 1
 
@@ -52,8 +56,4 @@
 
 #endif
 
-#if !defined(__LIBC_GUARDLESS_INCLUDE)
-#define _FLOAT_H 1
-#endif
-
 #endif
diff --git a/limits.h b/limits.h
index b8ae625..0ef495a 100644
--- a/limits.h
+++ b/limits.h
@@ -1,6 +1,10 @@
 #if !defined(_LIMITS_H) || defined(__LIBC_GUARDLESS_INCLUDE)
+#if !defined(__LIBC_GUARDLESS_INCLUDE)
+#define _LIMITS_H 1
+#endif
 
-#ifndef _LIMITS_H
+#ifndef __LIMITS_H_MACROS
+#define __LIMITS_H_MACROS 1
 
 #ifndef __LIBC_C_JOIN
 #   define __LIBC_C_EXPAND_JOIN(x, suffix) x ## suffix
@@ -46,8 +50,4 @@
 
 #endif
 
-#if !defined(__LIBC_GUARDLESS_INCLUDE)
-#define _LIMITS_H 1
-#endif
-
 #endif
diff --git a/stdalign.h b/stdalign.h
index 72ab984..abdea0c 100644
--- a/stdalign.h
+++ b/stdalign.h
@@ -1,6 +1,10 @@
 #if !defined(_STDALIGN_H) || defined(__LIBC_GUARDLESS_INCLUDE)
+#if !defined(__LIBC_GUARDLESS_INCLUDE)
+#define _STDALIGN_H 1
+#endif
 
-#ifndef _STDALIGN_H
+#ifndef __STDALIGN_H_MACROS
+#define __STDALIGN_H_MACROS 1
 
 #ifndef __cplusplus
 #  define alignas _Alignas
@@ -13,8 +17,4 @@
 
 #endif
 
-#if !defined(__LIBC_GUARDLESS_INCLUDE)
-#define _STDALIGN_H 1
-#endif
-
 #endif
diff --git a/stdarg.h b/stdarg.h
index cbc064d..e26da00 100644
--- a/stdarg.h
+++ b/stdarg.h
@@ -1,8 +1,12 @@
 #if !defined(_STDARG_H) || defined(__LIBC_GUARDLESS_INCLUDE)
+#if !defined(__LIBC_GUARDLESS_INCLUDE)
+#define _STDARG_H 1
+#endif
 
 typedef __builtin_va_list va_list;
 
-#ifndef _STDARG_H
+#ifndef __STDARG_H_MACROS
+#define __STDARG_H_MACROS 1
 
 #define va_start(v, l) __builtin_va_start(v, l)
 #define va_end(v) __builtin_va_end(v)
@@ -11,8 +15,4 @@ typedef __builtin_va_list va_list;
 
 #endif
 
-#if !defined(__LIBC_GUARDLESS_INCLUDE)
-#define _STDARG_H 1
-#endif
-
 #endif
diff --git a/stdbool.h b/stdbool.h
index 1878fd3..365536c 100644
--- a/stdbool.h
+++ b/stdbool.h
@@ -1,4 +1,10 @@
 #if !defined(_STDBOOL_H) || defined(__LIBC_GUARDLESS_INCLUDE)
+#if !defined(__LIBC_GUARDLESS_INCLUDE)
+#define _STDBOOL_H 1
+#endif
+
+#ifndef __STDBOOL_H_MACROS
+#define __STDBOOL_H_MACROS 1
 
 #ifndef __cplusplus
 #  define bool _Bool
@@ -7,14 +13,8 @@
 #  define false 0
 #endif
 
-#ifndef _STDBOOL_H
-
 #define __bool_true_false_are_defined 1
 
 #endif
 
-#if !defined(__LIBC_GUARDLESS_INCLUDE)
-#define _STDBOOL_H 1
-#endif
-
 #endif
diff --git a/stddef.h b/stddef.h
index 9fe871e..e087eaa 100644
--- a/stddef.h
+++ b/stddef.h
@@ -1,4 +1,7 @@
 #if !defined(_STDDEF_H) || defined(__LIBC_GUARDLESS_INCLUDE)
+#if !defined(__LIBC_GUARDLESS_INCLUDE)
+#define _STDDEF_H 1
+#endif
 
 typedef __SIZE_TYPE__ size_t;
 typedef __PTRDIFF_TYPE__ ptrdiff_t;
@@ -13,7 +16,8 @@ typedef decltype(nullptr) nullptr_t;
 enum class byte : unsigned char {};
 #endif
 
-#ifndef _STDDEF_H
+#ifndef __STDDEF_H_MACROS
+#define __STDDEF_H_MACROS 1
 
 #ifdef NULL
 #undef NULL
@@ -29,8 +33,4 @@ enum class byte : unsigned char {};
 
 #endif
 
-#if !defined(__LIBC_GUARDLESS_INCLUDE)
-#define _STDDEF_H 1
-#endif
-
 #endif
diff --git a/stdint.h b/stdint.h
index 3050992..6b993a3 100644
--- a/stdint.h
+++ b/stdint.h
@@ -1,4 +1,7 @@
 #if !defined(_STDINT_H) || defined(__LIBC_GUARDLESS_INCLUDE)
+#if !defined(__LIBC_GUARDLESS_INCLUDE)
+#define _STDINT_H 1
+#endif
 
 typedef __UINT8_TYPE__ uint8_t;
 typedef __UINT16_TYPE__ uint16_t;
@@ -36,7 +39,8 @@ typedef __INTPTR_TYPE__ intptr_t;
 typedef __UINTMAX_TYPE__ uintmax_t;
 typedef __INTMAX_TYPE__ intmax_t;
 
-#ifndef _STDINT_H
+#ifndef __STDINT_H_MACROS
+#define __STDINT_H_MACROS 1
 
 /* Clang and GCC have different mechanisms for INT32_C and friends. */
 #ifdef __clang__
@@ -139,8 +143,4 @@ typedef __INTMAX_TYPE__ intmax_t;
 
 #endif
 
-#if !defined(__LIBC_GUARDLESS_INCLUDE)
-#define _STDINT_H 1
-#endif
-
 #endif