fixed undefined behaviour (changing twice between sequence points

Author: robosam2003

README.md

@@ -29,7 +29,7 @@ For this reason, a check before popping is vital.
 (exampleFifo.fifo_status() == Fifo_STATUS::Fifo_EMPTY) ? /* Handle the fact that it's empty. */ : exampleFifo.pop();
 ```
 
-See `example.cpp` for a more examples.
+See `example.cpp` for more examples.
 
 
 ### Usage with Vector

dynamicFifo.tpp

@@ -56,11 +56,12 @@ Fifo_STATUS Fifo<T>::push(const T& item) {
     }
     // otherwise:
     elem[nextFree] = item;
-    if (((nextFree+1) % sz) == endPointer) {
+    if (((nextFree+1) % sz) == static_cast<unsigned int>(endPointer)) {
         nextFree = -1;
     }
     else{
-        nextFree = (++nextFree) % sz; // wrap around /:)
+        nextFree++;
+        nextFree = (nextFree) % sz; // wrap around /:)
     }
     return Fifo_STATUS::Fifo_GOOD;
 }
@@ -75,7 +76,8 @@ T Fifo<T>::pop() { /// Note: You should check the status of the fifo before call
     if (fifo_status()==Fifo_STATUS::Fifo_FULL) {
         nextFree=endPointer;
     }
-    endPointer = (++endPointer) % sz; // wrap around /:)
+    endPointer++;
+    endPointer = (endPointer) % sz; // wrap around /:)
     return r;
 }
 

example.cpp examples/example.cpp

@@ -87,7 +87,11 @@ int main() {
     // C-style casts. - does not resize the fifo.
     Fifo<double> e2 = (Fifo<double>) e1;
 
-    (e2.fifo_status() == Fifo_STATUS::Fifo_EMPTY) ? /* Handle the fact that it's empty. */ : e2.pop();
+
+    if (e2.fifo_status() == Fifo_STATUS::Fifo_EMPTY)
+        std::cout<<"It's empty";
+    else
+        e2.pop();
     std::cout << "e2 Free space: " << e2.free_space() << std::endl;
 
 #endif // DYNAMIC_FIFO_H