diff --git a/configure b/configure
index 9fa7068f..172225fe 100755
--- a/configure
+++ b/configure
@@ -2445,7 +2445,7 @@ appendLD () {
 	fi
 }
 
-appendCXX "-D_GNU_SOURCE -D_FORTIFY_SOURCE=2"
+appendCXX "-D_FORTIFY_SOURCE=2"
 
 case "${host_os}" in
 	freebsd*)
diff --git a/configure.in b/configure.in
index 48c1d1d8..72191e2e 100644
--- a/configure.in
+++ b/configure.in
@@ -39,7 +39,7 @@ appendLD () {
 	fi
 }
 
-appendCXX "-D_GNU_SOURCE -D_FORTIFY_SOURCE=2"
+appendCXX "-D_FORTIFY_SOURCE=2"
 
 case "${host_os}" in
 	freebsd*)