diff --git a/asn1c/tests/Makefile.am b/asn1c/tests/Makefile.am
index 11f9b25831fb660cd00bddbd329b72f279febf07..24d0a38f98e4585063e0ef938de27b3f9c6b6c80 100644
--- a/asn1c/tests/Makefile.am
+++ b/asn1c/tests/Makefile.am
@@ -11,7 +11,7 @@ else
 TESTS = check-*.c
 endif
 
-EXTRA_DIST = ${check_SCRIPTS} check-*.c*
+EXTRA_DIST = $(check_SCRIPTS) check-*.c*
 
 clean:
 	for t in test-*; do rm -rf $$t; done
diff --git a/asn1c/tests/check-25.c b/asn1c/tests/check-25.c
index 5660d05642b81125380d8d3a55da57e714511266..eba3ddf2558974c31765926336ab7cb44fb9e929 100644
--- a/asn1c/tests/check-25.c
+++ b/asn1c/tests/check-25.c
@@ -103,6 +103,7 @@ check(int is_ok, uint8_t *buf, int size, size_t consumed) {
 		assert(t.g->size == 3);
 		assert(t.g->buf[0] == 2);
 		assert(t.g->buf[1] == 147);
+		assert(t.g->buf[2] != 150);
 		assert(t.g->buf[2] == 148);
 
 		printf("%d\n", t.h->buf[3]);
diff --git a/asn1c/tests/check-35.c b/asn1c/tests/check-35.c
index 42354947234ef0b19b5b9f232ae98851e77da116..1d260f080adfd5ef270b4ef0724ed7b232fea435 100644
--- a/asn1c/tests/check-35.c
+++ b/asn1c/tests/check-35.c
@@ -155,7 +155,7 @@ buf_fill(const void *buffer, size_t size, void *app_key) {
 	return 0;
 }
 
-void
+static void
 compare(T_t *tp, uint8_t *cmp_buf, int cmp_buf_size) {
 	der_enc_rval_t erval;
 	int i;
diff --git a/asn1c/tests/check-41.c b/asn1c/tests/check-41.c
index d36ad1ec0dc58ccebff462bac8990ea3599022aa..fc2ce66f1f5adc00223cb658aca9895a542e1385 100644
--- a/asn1c/tests/check-41.c
+++ b/asn1c/tests/check-41.c
@@ -172,7 +172,7 @@ buf_fill(const void *buffer, size_t size, void *app_key) {
 	return 0;
 }
 
-void
+static void
 compare(T_t *tp, uint8_t *cmp_buf, int cmp_buf_size) {
 	der_enc_rval_t erval;
 	int i;
@@ -277,12 +277,9 @@ partial_read(uint8_t *buf, size_t size) {
 }
 
 int
-main(int ac, char **av) {
+main() {
 	T_t t;
 
-	(void)ac;	/* Unused argument */
-	(void)av;	/* Unused argument */
-
 	/* Check exact buf0 */
 	check(&t, buf0, sizeof(buf0), sizeof(buf0));
 	compare(&t, buf0_reconstr, sizeof(buf0_reconstr));
diff --git a/asn1c/tests/check-assembly.sh b/asn1c/tests/check-assembly.sh
index d9f4afed9fd48f685488f160b3e79dd3437ae3cd..f3461d3b8a40fa33b0cd0d499218a6de77ee4904 100755
--- a/asn1c/tests/check-assembly.sh
+++ b/asn1c/tests/check-assembly.sh
@@ -40,13 +40,13 @@ SRCS=`echo *.c*`
 OBJS1=\${SRCS:.c=.o}
 OBJS=\${OBJS1:.cc=.o}
 check-executable: \${OBJS}
-	\${CC} \${CFLAGS} -o check-executable \${OBJS}
+	\$(CC) \$(CFLAGS) -o check-executable \$(OBJS)
 .SUFFIXES:
 .SUFFIXES: .c .cc .o
 .c.o:
-	\${CC} \${CFLAGS} -o \$@ -c \$<
+	\$(CC) \$(CFLAGS) -o \$@ -c \$<
 .cc.o:
-	\${CXX} \${CXXFLAGS} -o \$@ -c \$<
+	\$(CXX) \$(CXXFLAGS) -o \$@ -c \$<
 check: check-executable
 	./check-executable
 clean: