4 files changed, 9 insertions, 11 deletions
diff --git a/icing/legacy/core/icing-core-types.h b/icing/legacy/core/icing-core-types.h
index cc12663..7db8408 100644
--- a/icing/legacy/core/icing-core-types.h
+++ b/icing/legacy/core/icing-core-types.h
@@ -21,9 +21,8 @@
 #ifndef ICING_LEGACY_CORE_ICING_CORE_TYPES_H_
 #define ICING_LEGACY_CORE_ICING_CORE_TYPES_H_
 
-#include <stdint.h>
-
 #include <cstddef>  // size_t not defined implicitly for all platforms.
+#include <cstdint>
 #include <vector>
 
 #include "icing/legacy/core/icing-compat.h"
diff --git a/icing/legacy/core/icing-string-util.cc b/icing/legacy/core/icing-string-util.cc
index 2eb64ac..ed06e03 100644
--- a/icing/legacy/core/icing-string-util.cc
+++ b/icing/legacy/core/icing-string-util.cc
@@ -13,12 +13,11 @@
 // limitations under the License.
 #include "icing/legacy/core/icing-string-util.h"
 
-#include <stdarg.h>
-#include <stddef.h>
-#include <stdint.h>
-#include <stdio.h>
-
 #include <algorithm>
+#include <cstdarg>
+#include <cstddef>
+#include <cstdint>
+#include <cstdio>
 #include <string>
 
 #include "icing/legacy/portable/icing-zlib.h"
diff --git a/icing/legacy/core/icing-string-util.h b/icing/legacy/core/icing-string-util.h
index 767e581..e5e4941 100644
--- a/icing/legacy/core/icing-string-util.h
+++ b/icing/legacy/core/icing-string-util.h
@@ -15,9 +15,8 @@
 #ifndef ICING_LEGACY_CORE_ICING_STRING_UTIL_H_
 #define ICING_LEGACY_CORE_ICING_STRING_UTIL_H_
 
-#include <stdarg.h>
-#include <stdint.h>
-
+#include <cstdarg>
+#include <cstdint>
 #include <string>
 
 #include "icing/legacy/core/icing-compat.h"
diff --git a/icing/legacy/core/icing-timer.h b/icing/legacy/core/icing-timer.h
index 49ba9ad..af38912 100644
--- a/icing/legacy/core/icing-timer.h
+++ b/icing/legacy/core/icing-timer.h
@@ -16,7 +16,8 @@
 #define ICING_LEGACY_CORE_ICING_TIMER_H_
 
 #include <sys/time.h>
-#include <time.h>
+
+#include <ctime>
 
 namespace icing {
 namespace lib {