diff --git a/library/x509_crt.c b/library/x509_crt.c
index c373913..e41cbbe 100644
--- a/library/x509_crt.c
+++ b/library/x509_crt.c
@@ -1668,20 +1668,24 @@
 #endif /* MBEDTLS_FS_IO */
 
 #if !defined(MBEDTLS_X509_REMOVE_INFO)
-#define PRINT_ITEM(i)                           \
-    {                                           \
-        ret = mbedtls_snprintf(p, n, "%s" i, sep);    \
-        MBEDTLS_X509_SAFE_SNPRINTF;                        \
-        sep = ", ";                             \
-    }
+#define PRINT_ITEM(i)                               \
+    do {                                            \
+        ret = mbedtls_snprintf(p, n, "%s" i, sep);  \
+        MBEDTLS_X509_SAFE_SNPRINTF;                 \
+        sep = ", ";                                 \
+    } while (0)
 
-#define CERT_TYPE(type, name)                    \
-    if (ns_cert_type & (type))                 \
-    PRINT_ITEM(name);
+#define CERT_TYPE(type, name)          \
+    do {                               \
+        if (ns_cert_type & (type))     \
+        PRINT_ITEM(name);              \
+    } while (0)
 
-#define KEY_USAGE(code, name)    \
-    if (key_usage & (code))    \
-    PRINT_ITEM(name);
+#define KEY_USAGE(code, name)      \
+    do {                           \
+        if (key_usage & (code))    \
+        PRINT_ITEM(name);          \
+    } while (0)
 
 static int x509_info_ext_key_usage(char **buf, size_t *size,
                                    const mbedtls_x509_sequence *extended_key_usage)