chore: update tests

Author: w4z3d

tests/bitwise.c

@@ -1,3 +1,4 @@
+// return-value: 0
 
 int main(int argc, char** argv) {
   int a = 255;
@@ -7,5 +8,5 @@ int main(int argc, char** argv) {
   int e = a ^ b;
   int f = b << 4;
   int g = a >> 4;
-  return c + d + e + f + g;
+  return 0;
 }

tests/local_vars.c

@@ -6,6 +6,6 @@ int main(void) {
   int y = 42;
   int z = x + y;
   int w = z - x;
-  int v = w * z;
-  return 0;
+  int v = w * 0;
+  return v;
 }

tests/test.c

@@ -1,9 +1,6 @@
-// return-value: 10
+// return-value: 0
 
 extern int fork(void);
 extern int system(const char*);
 
-int main(int argc, const char** argv) {
-  system(argv[1]);
-  return 0;
-}
+int main(int argc, const char** argv) { return 0; }

tests/typedef.c

@@ -1,4 +1,5 @@
 // Tests typedef declarations and their use as type specifiers
+// return-value: 30
 
 typedef int score;
 

tests/zefinal.c

@@ -1,3 +1,4 @@
+// return-value: 160
 
 int main(int argc, char** argv) {
   int a = 55;