A correction to originally overlooked NaN handling in numba implementation

Author: viable-alternative

Diff for: pandas/core/_numba/kernels/min_max_.py

@@ -118,8 +118,10 @@ def cmp(a: Any, b: Any, is_max: bool) -> bool:
                 Q.append(k)
 
         if not Q or (this_start > valid_start):
-            output[i] = np.nan
-            na_pos.append(i)
+            if values.dtype.kind != "i":
+                output[i] = np.nan
+            else:
+                na_pos.append(i)
         elif Q[0] >= this_start:
             output[i] = values[Q[0]]
         else: