diff --git a/sys/compat/linuxkpi/common/include/linux/overflow.h b/sys/compat/linuxkpi/common/include/linux/overflow.h
--- a/sys/compat/linuxkpi/common/include/linux/overflow.h
+++ b/sys/compat/linuxkpi/common/include/linux/overflow.h
@@ -34,18 +34,9 @@
 #include <sys/stdint.h>
 #include <sys/types.h>
 
-#ifndef	__has_builtin
-#define	__has_builtin(x)	0
-#endif
-
-#if __has_builtin(__builtin_add_overflow)
 #define check_add_overflow(a, b, c)		\
 	__builtin_add_overflow(a, b, c)
-#else
-#error "Compiler does not support __builtin_add_overflow"
-#endif
 
-#if __has_builtin(__builtin_mul_overflow)
 #define check_mul_overflow(a, b, c)	\
 	__builtin_mul_overflow(a, b, c)
 
@@ -58,8 +49,5 @@
 		retval = SIZE_MAX;
 	return (retval);
 }
-#else
-#error "Compiler does not support __builtin_mul_overflow"
-#endif
 
 #endif	/* __LINUX_OVERFLOW_H__ */