Suppress two CLANG Analyze warning (#4291)

Summary:
Suppress two CLANG analyze warnings. They don't seem to be real bugs
Pull Request resolved: https://github.com/facebook/rocksdb/pull/4291

Differential Revision: D9407333

Pulled By: siying

fbshipit-source-id: 2ed63d88fa0b217fdccb1572d7508467c2203dc8

table/block_based_table_reader.cc

@@ -2840,7 +2840,6 @@ Status BlockBasedTable::DumpTable(WritableFile* out_file,
         "  ");
     out_file->Append(table_properties->ToString("\n  ", ": ").c_str());
     out_file->Append("\n");
-  }
 
     // Output Filter blocks
     if (!rep_->filter && !table_properties->filter_policy_name.empty()) {
@@ -2857,8 +2856,8 @@ Status BlockBasedTable::DumpTable(WritableFile* out_file,
           Slice dummy_comp_dict;
           BlockFetcher block_fetcher(
               rep_->file.get(), nullptr /* prefetch_buffer */, rep_->footer,
-            ReadOptions(), handle, &block, rep_->ioptions, false /*decompress*/,
+              ReadOptions(), handle, &block, rep_->ioptions,
-            dummy_comp_dict /*compression dict*/,
+              false /*decompress*/, dummy_comp_dict /*compression dict*/,
               rep_->persistent_cache_options);
           s = block_fetcher.ReadBlockContents();
           if (!s.ok()) {
@@ -2870,6 +2869,7 @@ Status BlockBasedTable::DumpTable(WritableFile* out_file,
         }
       }
     }
+  }
   if (rep_->filter) {
     out_file->Append(
         "Filter Details:\n"

table/block_fetcher.cc

@@ -169,6 +169,7 @@ void BlockFetcher::GetBlockContents() {
     // page can be either uncompressed or compressed, the buffer either stack
     // or heap provided. Refer to https://github.com/facebook/rocksdb/pull/4096
     if (got_from_prefetch_buffer_ || used_buf_ == &stack_buf_[0]) {
+      assert(used_buf_ != heap_buf_.get());
       heap_buf_.reset(new char[block_size_ + kBlockTrailerSize]);
       memcpy(heap_buf_.get(), used_buf_, block_size_ + kBlockTrailerSize);
     }