diff --git a/libc/include/stdatomic.h b/libc/include/stdatomic.h
index 2c4f1ce..8347f83 100644
--- a/libc/include/stdatomic.h
+++ b/libc/include/stdatomic.h
@@ -32,22 +32,13 @@
 
 #include <sys/cdefs.h>
 
-#if defined(__GNUC__) && !defined(__GNUC_PREREQ)
-/* Duplicate definition here, since the mingw sys/cdefs.h omits the  */
-/* definition, and this needs to be usable there.                    */
-#define	__GNUC_PREREQ(x, y)    \
-	((__GNUC__ == (x) && __GNUC_MINOR__ >= (y)) || (__GNUC__ > (x)))
-#endif /* __GNUC__ && ... */
-
 #if defined(__cplusplus) && __cplusplus >= 201103L && defined(_USING_LIBCXX)
 # ifdef __clang__
 #  if __has_feature(cxx_atomic)
 #   define _STDATOMIC_HAVE_ATOMIC
 #  endif
 # else /* gcc */
-#  if __GNUC_PREREQ(4, 7)
-#   define _STDATOMIC_HAVE_ATOMIC
-#  endif
+#  define _STDATOMIC_HAVE_ATOMIC
 # endif
 #endif
 
@@ -166,14 +157,7 @@
 #  define __HAS_BUILTIN_SYNC_SWAP
 # endif
 #else
-# if __GNUC_PREREQ(4, 7)
-#  define	__GNUC_ATOMICS
-# else
-#  define	__SYNC_ATOMICS
-#  ifdef __cplusplus
-#   define       __ATOMICS_AVOID_DOT_INIT
-#  endif
-# endif
+# define __GNUC_ATOMICS
 #endif
 
 /*
@@ -182,53 +166,33 @@
 
 #ifdef __GCC_ATOMIC_BOOL_LOCK_FREE
 #define	ATOMIC_BOOL_LOCK_FREE		__GCC_ATOMIC_BOOL_LOCK_FREE
-#elif defined(__SYNC_ATOMICS)
-#define	ATOMIC_BOOL_LOCK_FREE           2 /* For all modern platforms */
 #endif
 #ifdef __GCC_ATOMIC_CHAR_LOCK_FREE
 #define	ATOMIC_CHAR_LOCK_FREE		__GCC_ATOMIC_CHAR_LOCK_FREE
-#elif defined(__SYNC_ATOMICS)
-#define	ATOMIC_CHAR_LOCK_FREE           2
 #endif
 #ifdef __GCC_ATOMIC_CHAR16_T_LOCK_FREE
 #define	ATOMIC_CHAR16_T_LOCK_FREE	__GCC_ATOMIC_CHAR16_T_LOCK_FREE
-#elif defined(__SYNC_ATOMICS)
-#define	ATOMIC_CHAR16_T_LOCK_FREE       2
 #endif
 #ifdef __GCC_ATOMIC_CHAR32_T_LOCK_FREE
 #define	ATOMIC_CHAR32_T_LOCK_FREE	__GCC_ATOMIC_CHAR32_T_LOCK_FREE
-#elif defined(__SYNC_ATOMICS)
-#define	ATOMIC_CHAR32_T_LOCK_FREE       2
 #endif
 #ifdef __GCC_ATOMIC_WCHAR_T_LOCK_FREE
 #define	ATOMIC_WCHAR_T_LOCK_FREE	__GCC_ATOMIC_WCHAR_T_LOCK_FREE
-#elif defined(__SYNC_ATOMICS)
-#define	ATOMIC_WCHAR_T_LOCK_FREE        2
 #endif
 #ifdef __GCC_ATOMIC_SHORT_LOCK_FREE
 #define	ATOMIC_SHORT_LOCK_FREE		__GCC_ATOMIC_SHORT_LOCK_FREE
-#elif defined(__SYNC_ATOMICS)
-#define	ATOMIC_SHORT_LOCK_FREE          2
 #endif
 #ifdef __GCC_ATOMIC_INT_LOCK_FREE
 #define	ATOMIC_INT_LOCK_FREE		__GCC_ATOMIC_INT_LOCK_FREE
-#elif defined(__SYNC_ATOMICS)
-#define	ATOMIC_INT_LOCK_FREE            2
 #endif
 #ifdef __GCC_ATOMIC_LONG_LOCK_FREE
 #define	ATOMIC_LONG_LOCK_FREE		__GCC_ATOMIC_LONG_LOCK_FREE
-#elif defined(__SYNC_ATOMICS)
-#define	ATOMIC_LONG_LOCK_FREE           2
 #endif
 #ifdef __GCC_ATOMIC_LLONG_LOCK_FREE
 #define	ATOMIC_LLONG_LOCK_FREE		__GCC_ATOMIC_LLONG_LOCK_FREE
-#elif defined(__SYNC_ATOMICS)
-#define	ATOMIC_LLONG_LOCK_FREE          1 /* maybe */
 #endif
 #ifdef __GCC_ATOMIC_POINTER_LOCK_FREE
 #define	ATOMIC_POINTER_LOCK_FREE	__GCC_ATOMIC_POINTER_LOCK_FREE
-#elif defined(__SYNC_ATOMICS)
-#define	ATOMIC_POINTER_LOCK_FREE        2
 #endif
 
 /*
@@ -239,11 +203,7 @@
 #define	ATOMIC_VAR_INIT(value)		(value)
 #define	atomic_init(obj, value)		__c11_atomic_init(obj, value)
 #else
-#ifdef __ATOMICS_AVOID_DOT_INIT
-#define	ATOMIC_VAR_INIT(value)		{ value }
-#else
 #define	ATOMIC_VAR_INIT(value)		{ .__val = (value) }
-#endif
 #define	atomic_init(obj, value)		((void)((obj)->__val = (value)))
 #endif