diff --git a/src/dsql/pass1.cpp b/src/dsql/pass1.cpp
index dd9bd51bb0..7140db362d 100644
--- a/src/dsql/pass1.cpp
+++ b/src/dsql/pass1.cpp
@@ -931,13 +931,15 @@ dsql_nod* PASS1_node(dsql_req* request, dsql_nod* input, bool proc_flag)
 	case nod_current_timestamp:
 		{
 			dsql_nod* const_node = input->nod_arg[0];
-			fb_assert(const_node->nod_type == nod_constant);
-			const int precision = (int)(IPTR) const_node->nod_arg[0];
-			fb_assert(precision >= 0);
-			// We pass precision as a single byte, hence a check
-			// to avoid overflows
-			if (precision > MAX_UCHAR) {
-				const_node->nod_arg[0] = (dsql_nod*)(IPTR) MAX_UCHAR;
+			if (const_node) {
+				fb_assert(const_node->nod_type == nod_constant);
+				const int precision = (int)(IPTR) const_node->nod_arg[0];
+				fb_assert(precision >= 0);
+				// We pass precision as a single byte, hence a check
+				// to avoid overflows
+				if (precision > MAX_UCHAR) {
+					const_node->nod_arg[0] = (dsql_nod*)(IPTR) MAX_UCHAR;
+				}
 			}
 		}
 		break;