diff --git a/include/stdbool.h b/include/stdbool.h
index 267e1ad2a1a0..2879da798da6 100644
--- a/include/stdbool.h
+++ b/include/stdbool.h
@@ -37,9 +37,6 @@
 #define	true	1
 
 #define	bool	_Bool
-#if __STDC_VERSION__ < 199901L && __GNUC__ < 3 && !defined(__INTEL_COMPILER)
-typedef	int	_Bool;
-#endif
 
 #endif /* !__cplusplus */
 #endif /* __bool_true_false_are_defined */
diff --git a/include/stdlib.h b/include/stdlib.h
index 045a9fda9cfb..ca96c06b83b7 100644
--- a/include/stdlib.h
+++ b/include/stdlib.h
@@ -253,7 +253,7 @@ extern void (*malloc_message)(void *, const char *);
  * On platforms where alloca() is not in libc, programs which use it
  * will fail to link when compiled with non-GNU compilers.
  */
-#if __GNUC__ >= 2 || defined(__INTEL_COMPILER)
+#if __GNUC__ >= 2
 #undef  alloca	/* some GNU bits try to get cute and define this on their own */
 #define alloca(sz) __builtin_alloca(sz)
 #endif
diff --git a/sys/sys/types.h b/sys/sys/types.h
index 61191bf8996c..c026fa023bd0 100644
--- a/sys/sys/types.h
+++ b/sys/sys/types.h
@@ -300,9 +300,6 @@ typedef	struct vm_page	*vm_page_t;
 #define	__bool_true_false_are_defined	1
 #define	false	0
 #define	true	1
-#if __STDC_VERSION__ < 199901L && __GNUC__ < 3 && !defined(__INTEL_COMPILER)
-typedef	int	_Bool;
-#endif
 typedef	_Bool	bool;
 #endif /* !__bool_true_false_are_defined && !__cplusplus */
 #endif /* KERNEL || _STANDALONE */