diff --git a/libc/arch-arm/include/machine/limits.h b/libc/arch-arm/include/machine/limits.h
index f9c04fa..ddeb583 100644
--- a/libc/arch-arm/include/machine/limits.h
+++ b/libc/arch-arm/include/machine/limits.h
@@ -39,9 +39,6 @@
 
 #define	MB_LEN_MAX	1		/* no multibyte characters */
 
-#ifndef	SIZE_MAX
-#define	SIZE_MAX	UINT_MAX	/* max value for a size_t */
-#endif
 #ifndef SSIZE_MAX
 #define	SSIZE_MAX	INT_MAX		/* max value for a ssize_t */
 #endif
diff --git a/libc/arch-arm64/include/machine/limits.h b/libc/arch-arm64/include/machine/limits.h
index ecddb01..c7fa053 100644
--- a/libc/arch-arm64/include/machine/limits.h
+++ b/libc/arch-arm64/include/machine/limits.h
@@ -44,9 +44,6 @@
 #define	LONGLONG_MAX	9223372036854775807LL
 #define	ULONGLONG_MAX	18446744073709551615ULL
 
-#ifndef	SIZE_MAX
-#define	SIZE_MAX	ULONGLONG_MAX	/* max value for a size_t */
-#endif
 #ifndef SSIZE_MAX
 #define	SSIZE_MAX	LONGLONG_MAX		/* max value for a ssize_t */
 #endif
diff --git a/libc/arch-mips/include/machine/limits.h b/libc/arch-mips/include/machine/limits.h
index 339444d..a37a5a5 100644
--- a/libc/arch-mips/include/machine/limits.h
+++ b/libc/arch-mips/include/machine/limits.h
@@ -38,9 +38,6 @@
 
 #define	MB_LEN_MAX	6		/* Allow 31 bit UTF2 */
 
-#ifndef	SIZE_MAX
-#define	SIZE_MAX	ULONG_MAX	/* max value for a size_t */
-#endif
 #define	SSIZE_MAX	LONG_MAX	/* max value for a ssize_t */
 
 #if __BSD_VISIBLE
diff --git a/libc/arch-mips64/include/machine/limits.h b/libc/arch-mips64/include/machine/limits.h
index 339444d..a37a5a5 100644
--- a/libc/arch-mips64/include/machine/limits.h
+++ b/libc/arch-mips64/include/machine/limits.h
@@ -38,9 +38,6 @@
 
 #define	MB_LEN_MAX	6		/* Allow 31 bit UTF2 */
 
-#ifndef	SIZE_MAX
-#define	SIZE_MAX	ULONG_MAX	/* max value for a size_t */
-#endif
 #define	SSIZE_MAX	LONG_MAX	/* max value for a ssize_t */
 
 #if __BSD_VISIBLE
diff --git a/libc/arch-x86/include/machine/limits.h b/libc/arch-x86/include/machine/limits.h
index 86fd854..1e702de 100644
--- a/libc/arch-x86/include/machine/limits.h
+++ b/libc/arch-x86/include/machine/limits.h
@@ -39,9 +39,6 @@
 
 #define	MB_LEN_MAX	1		/* no multibyte characters */
 
-#ifndef	SIZE_MAX
-#define	SIZE_MAX	UINT_MAX	/* max value for a size_t */
-#endif
 #ifndef SSIZE_MAX
 #define	SSIZE_MAX	INT_MAX		/* max value for a ssize_t */
 #endif
diff --git a/libc/arch-x86_64/include/machine/limits.h b/libc/arch-x86_64/include/machine/limits.h
index a8c4a88..d01fc5b 100644
--- a/libc/arch-x86_64/include/machine/limits.h
+++ b/libc/arch-x86_64/include/machine/limits.h
@@ -37,9 +37,6 @@
 #include <sys/cdefs.h>
 
 #if __POSIX_VISIBLE || __XPG_VISIBLE
-#ifndef	SIZE_MAX
-#define SIZE_MAX	ULONG_MAX	/* max value for a size_t */
-#endif
 #define SSIZE_MAX	LONG_MAX	/* max value for a ssize_t */
 #endif