diff --git a/tests/abitest.c b/tests/abitest.c
index 7b12144..d3e151f 100644
--- a/tests/abitest.c
+++ b/tests/abitest.c
@@ -339,8 +339,8 @@ static int stdarg_test(void) {
   "#include <stdarg.h>\n"
   "typedef struct {long long a, b, c;} stdarg_test_struct_type;\n"
   "void f(int n_int, int n_float, int n_struct, ...) {\n"
-  "  int i, ti;\n"
-  "  double td;\n"
+  "  int i, ti = 0;\n"
+  "  double td = 0.0;\n"
   "  stdarg_test_struct_type ts = {0,0,0}, tmp;\n"
   "  va_list ap;\n"
   "  va_start(ap, n_struct);\n"