diff --git a/SystemInformation.cxx b/SystemInformation.cxx
index 9e2a93d7c296c1b81ff92bad792b5a2e4853139e..8621d2e77609ede105a6a0150381736fee1449cd 100644
--- a/SystemInformation.cxx
+++ b/SystemInformation.cxx
@@ -1471,7 +1471,7 @@ int SystemInformationImplementation::GetFullyQualifiedDomainName(
       {
       char host[NI_MAXHOST]={'\0'};
 
-      int addrlen
+      socklen_t addrlen
         = (fam==AF_INET?sizeof(struct sockaddr_in):sizeof(struct sockaddr_in6));
 
       ierr=getnameinfo(