dnl integral types on older systems that fail to provide intN_t and
dnl uintN_t typedefs.
dnl
-AC_CHECK_SIZEOF(short)
-AC_CHECK_SIZEOF(int)
-AC_CHECK_SIZEOF(long)
-AC_CHECK_SIZEOF(long long)
-AC_CHECK_SIZEOF(void *)
+AC_CHECK_SIZEOF([short])
+AC_CHECK_SIZEOF([int])
+AC_CHECK_SIZEOF([long])
+AC_CHECK_SIZEOF([long long])
+AC_CHECK_SIZEOF([void *])
dnl
dnl Checks for non-universal or system-specific types.