diff --git a/src/build_log.cc b/src/build_log.cc
index 073d2fe81e..4d6ee2823a 100644
--- a/src/build_log.cc
+++ b/src/build_log.cc
@@ -72,8 +72,7 @@ BuildLog::LogEntry::LogEntry(const string& output, uint64_t command_hash,
     start_time(start_time), end_time(end_time), mtime(mtime)
 {}
 
-BuildLog::BuildLog()
-  : log_file_(NULL), needs_recompaction_(false) {}
+BuildLog::BuildLog() = default;
 
 BuildLog::~BuildLog() {
   Close();
diff --git a/src/build_log.h b/src/build_log.h
index 1223c2a16a..36f3846d3c 100644
--- a/src/build_log.h
+++ b/src/build_log.h
@@ -57,10 +57,10 @@ struct BuildLog {
 
   struct LogEntry {
     std::string output;
-    uint64_t command_hash;
-    int start_time;
-    int end_time;
-    TimeStamp mtime;
+    uint64_t command_hash = 0;
+    int start_time = 0;
+    int end_time = 0;
+    TimeStamp mtime = 0;
 
     static uint64_t HashCommand(StringPiece command);
 
@@ -99,9 +99,9 @@ struct BuildLog {
   bool OpenForWriteIfNeeded();
 
   Entries entries_;
-  FILE* log_file_;
+  FILE* log_file_ = nullptr;
   std::string log_file_path_;
-  bool needs_recompaction_;
+  bool needs_recompaction_ = false;
 };
 
 #endif // NINJA_BUILD_LOG_H_