diff --git a/libasn1compiler/asn1c_constraint.c b/libasn1compiler/asn1c_constraint.c
index 0b502b6..df9ca68 100644
--- a/libasn1compiler/asn1c_constraint.c
+++ b/libasn1compiler/asn1c_constraint.c
@@ -195,6 +195,9 @@
 			OUT("1 /* No applicable constraints whatsoever */");
 			OUT(") {\n");
 			INDENT(-1);
+			if(produce_st) {
+				INDENTED(OUT("(void)st; /* Unused variable */\n"));
+			}
 			INDENTED(OUT("/* Nothing is here. See below */\n"));
 			OUT("}\n");
 			OUT("\n");
diff --git a/tests/125-bitstring-constraint-OK.asn1.-P b/tests/125-bitstring-constraint-OK.asn1.-P
index 6b5c762..c464138 100644
--- a/tests/125-bitstring-constraint-OK.asn1.-P
+++ b/tests/125-bitstring-constraint-OK.asn1.-P
@@ -42,6 +42,7 @@
 	
 	
 	if(1 /* No applicable constraints whatsoever */) {
+		(void)st; /* Unused variable */
 		/* Nothing is here. See below */
 	}
 	
diff --git a/tests/90-cond-int-type-OK.asn1.-Pfwide-types b/tests/90-cond-int-type-OK.asn1.-Pfwide-types
index f170d99..30633fd 100644
--- a/tests/90-cond-int-type-OK.asn1.-Pfwide-types
+++ b/tests/90-cond-int-type-OK.asn1.-Pfwide-types
@@ -159,6 +159,7 @@
 	
 	
 	if(1 /* No applicable constraints whatsoever */) {
+		(void)st; /* Unused variable */
 		/* Nothing is here. See below */
 	}