diff --git a/config/always-no-unused-but-set-variable.m4 b/config/always-no-unused-but-set-variable.m4
index 0e2634da2696..4a3ceb614af8 100644
--- a/config/always-no-unused-but-set-variable.m4
+++ b/config/always-no-unused-but-set-variable.m4
@@ -12,7 +12,7 @@ AC_DEFUN([ZFS_AC_CONFIG_ALWAYS_NO_UNUSED_BUT_SET_VARIABLE], [
 	saved_flags="$CFLAGS"
 	CFLAGS="$CFLAGS -Wunused-but-set-variable"
 
-	AC_RUN_IFELSE(AC_LANG_PROGRAM( [], []),
+	AC_RUN_IFELSE([AC_LANG_PROGRAM([], [])],
 	[
 		NO_UNUSED_BUT_SET_VARIABLE=-Wno-unused-but-set-variable
 		AC_MSG_RESULT([yes])
diff --git a/config/user-frame-larger-than.m4 b/config/user-frame-larger-than.m4
index 3384f50e4a46..7ad86220d7aa 100644
--- a/config/user-frame-larger-than.m4
+++ b/config/user-frame-larger-than.m4
@@ -7,7 +7,7 @@ AC_DEFUN([ZFS_AC_CONFIG_USER_FRAME_LARGER_THAN], [
 	saved_flags="$CFLAGS"
 	CFLAGS="$CFLAGS -Wframe-larger-than=1024"
 
-	AC_RUN_IFELSE(AC_LANG_PROGRAM( [], []),
+	AC_RUN_IFELSE([AC_LANG_PROGRAM([], [])],
 	[
 		FRAME_LARGER_THAN=-Wframe-larger-than=1024
 		AC_MSG_RESULT([yes])
diff --git a/config/user-libblkid.m4 b/config/user-libblkid.m4
index 8934d0ab80ed..276587fd3589 100644
--- a/config/user-libblkid.m4
+++ b/config/user-libblkid.m4
@@ -39,7 +39,7 @@ AC_DEFUN([ZFS_AC_CONFIG_USER_LIBBLKID], [
 			saved_LDFLAGS="$LDFLAGS"
 			LDFLAGS="-lblkid"
 
-			AC_RUN_IFELSE(AC_LANG_PROGRAM(
+			AC_RUN_IFELSE([AC_LANG_PROGRAM(
 			[
 				#include <stdio.h>
 				#include <blkid/blkid.h>
@@ -66,7 +66,7 @@ AC_DEFUN([ZFS_AC_CONFIG_USER_LIBBLKID], [
 
 				free(value);
 				blkid_put_cache(cache);
-			]),
+			])],
 			[
 				rm -f $ZFS_DEV
 				AC_MSG_RESULT([yes])
diff --git a/config/user-nptl_guard_within_stack.m4 b/config/user-nptl_guard_within_stack.m4
index d094da7332ca..421eb1c0553d 100644
--- a/config/user-nptl_guard_within_stack.m4
+++ b/config/user-nptl_guard_within_stack.m4
@@ -12,7 +12,7 @@ AC_DEFUN([ZFS_AC_CONFIG_USER_STACK_GUARD], [
 	saved_LDFLAGS="$LDFLAGS"
 	LDFLAGS="-lpthread"
 
-	AC_RUN_IFELSE(AC_LANG_PROGRAM(
+	AC_RUN_IFELSE([AC_LANG_PROGRAM(
 	[
 		#include <pthread.h>
 		#include <sys/resource.h>
@@ -25,7 +25,7 @@ AC_DEFUN([ZFS_AC_CONFIG_USER_STACK_GUARD], [
 
 		void * func(void *arg)
 		{
-			char buf[[[BUFSIZE]]];
+			char buf[[BUFSIZE]];
 		}
 	],
 	[
@@ -41,7 +41,7 @@ AC_DEFUN([ZFS_AC_CONFIG_USER_STACK_GUARD], [
 		pthread_attr_setguardsize(&attr, PAGESIZE);
 		pthread_create(&tid, &attr, func, NULL);
 		pthread_join(tid, NULL);
-	]),
+	])],
 	[
 		AC_MSG_RESULT([no])
 	],