diff --git a/include/site/linux b/include/site/linux
index ac34d30f6c..492d1ddde1 100644
--- a/include/site/linux
+++ b/include/site/linux
@@ -9,6 +9,8 @@ ac_cv_func__exit=yes
 ac_cv_func_bcopy=yes
 ac_cv_func_bzero=yes
 ac_cv_func_bcmp=yes
+ac_cv_func_creal=yes
+ac_cv_func_cimag=yes
 ac_cv_func_fchmod=yes
 ac_cv_func_getaddrinfo=yes
 ac_cv_func_getcwd=yes