diff --git a/libavcodec/eval.c b/libavcodec/eval.c
index e6394c39c157f0edbaccea6f2e324c7e60ddd2b2..da4876375dd676eb45487346b28eb6164d18bd82 100644
--- a/libavcodec/eval.c
+++ b/libavcodec/eval.c
@@ -451,7 +451,7 @@ static const char *const_names[]={
     "E",
     0
 };
-main(void){
+int main(void){
     int i;
     printf("%f == 12.7\n", ff_eval("1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)", const_values, const_names, NULL, NULL, NULL, NULL, NULL));
     printf("%f == 0.931322575\n", ff_eval("80G/80Gi", const_values, const_names, NULL, NULL, NULL, NULL, NULL));
@@ -461,5 +461,6 @@ main(void){
             ff_eval("1+(5-2)^(3-1)+1/2+sin(PI)-max(-2.2,-3.1)", const_values, const_names, NULL, NULL, NULL, NULL, NULL);
         STOP_TIMER("ff_eval")
     }
+    return 0;
 }
 #endif