diff --git a/common/utils/oai_asn1.h b/common/utils/oai_asn1.h
index 573fa94d75..600aea1392 100644
--- a/common/utils/oai_asn1.h
+++ b/common/utils/oai_asn1.h
@@ -216,7 +216,10 @@ static inline uint64_t BIT_STRING_to_uint64(const BIT_STRING_t *asn) {
 
 #define asn1cSeqAdd(VaR, PtR) if (ASN_SEQUENCE_ADD(VaR,PtR)!=0) AssertFatal(false, "ASN.1 encoding error " #VaR "\n")
 #define asn1cCallocOne(VaR, VaLue) \
-  VaR = calloc(1,sizeof(*VaR)); *VaR=VaLue
+  do {                             \
+    VaR = calloc(1,sizeof(*VaR));  \
+    *VaR = VaLue;                  \
+  } while (0)
 #define asn1cCalloc(VaR, lOcPtr) \
   typeof(VaR) lOcPtr = VaR = calloc(1,sizeof(*VaR))
 #define asn1cSequenceAdd(VaR, TyPe, lOcPtr) \