diff --git a/tests/Regression/bz488748-inet6-opt-init-sets-incorrect-header-len/runtest.sh b/tests/Regression/bz488748-inet6-opt-init-sets-incorrect-header-len/runtest.sh
index 44962e1..3649de7 100755
--- a/tests/Regression/bz488748-inet6-opt-init-sets-incorrect-header-len/runtest.sh
+++ b/tests/Regression/bz488748-inet6-opt-init-sets-incorrect-header-len/runtest.sh
@@ -34,7 +34,7 @@ PACKAGE="glibc"
 rlJournalStart
 rlPhaseStartSetup
   rlAssertRpm $PACKAGE
-  rlRun 'gcc optinit.c -o optinit' 0 "Compiling the testcase"
+  rlRun 'gcc -D_GNU_SOURCE optinit.c -o optinit' 0 "Compiling the testcase"
 rlPhaseEnd
 
 rlPhaseStartTest