Make sure assert(false) handles failures too (#7483)

Summary:
In opt mode, assertions are just no-ops. Therefore, we need to report errors instead of just doing an `assert(false)`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7483

Test Plan: make check

Reviewed By: anand1976

Differential Revision: D24142725

Pulled By: riversand963

fbshipit-source-id: 5629556dbe29f00dd09e30a7d5df5e6cf09ee435

db/compaction/compaction_picker_universal.cc

@@ -996,6 +996,9 @@ Compaction* UniversalCompactionBuilder::PickCompactionToOldest(
       comp_reason_print_string = "size amp";
     } else {
       assert(false);
+      comp_reason_print_string = "unknown: ";
+      comp_reason_print_string.append(
+          std::to_string(static_cast<int>(compaction_reason)));
     }
 
     char file_num_buf[256];

db/db_iter.cc

@@ -384,8 +384,11 @@ bool DBIter::FindNextUserEntryInternal(bool skipping_saved_key,
             }
             break;
           default:
-            assert(false);
-            break;
+            valid_ = false;
+            status_ = Status::Corruption(
+                "Unknown value type: " +
+                std::to_string(static_cast<unsigned int>(ikey_.type)));
+            return false;
         }
       }
     } else {
@@ -556,7 +559,11 @@ bool DBIter::MergeValuesNewToOld() {
       valid_ = false;
       return false;
     } else {
-      assert(false);
+      valid_ = false;
+      status_ = Status::Corruption(
+          "Unrecognized value type: " +
+          std::to_string(static_cast<unsigned int>(ikey.type)));
+      return false;
     }
   }
 
@@ -832,7 +839,11 @@ bool DBIter::FindValueForCurrentKey() {
         }
         break;
       default:
-        assert(false);
+        valid_ = false;
+        status_ = Status::Corruption(
+            "Unknown value type: " +
+            std::to_string(static_cast<unsigned int>(last_key_entry_type)));
+        return false;
     }
 
     PERF_COUNTER_ADD(internal_key_skipped_count, 1);
@@ -898,8 +909,11 @@ bool DBIter::FindValueForCurrentKey() {
       is_blob_ = true;
       break;
     default:
-      assert(false);
-      break;
+      valid_ = false;
+      status_ = Status::Corruption(
+          "Unknown value type: " +
+          std::to_string(static_cast<unsigned int>(last_key_entry_type)));
+      return false;
   }
   if (!s.ok()) {
     valid_ = false;
@@ -1048,7 +1062,11 @@ bool DBIter::FindValueForCurrentKeyUsingSeek() {
       valid_ = false;
       return false;
     } else {
-      assert(false);
+      valid_ = false;
+      status_ = Status::Corruption(
+          "Unknown value type: " +
+          std::to_string(static_cast<unsigned int>(ikey.type)));
+      return false;
     }
   }