diff --git a/llvm/lib/Fuzzer/FuzzerCrossOver.cpp b/llvm/lib/Fuzzer/FuzzerCrossOver.cpp
index 87ad555d3141..94af6d547edc 100644
--- a/llvm/lib/Fuzzer/FuzzerCrossOver.cpp
+++ b/llvm/lib/Fuzzer/FuzzerCrossOver.cpp
@@ -10,6 +10,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "FuzzerInternal.h"
+#include <algorithm>
 
 namespace fuzzer {
 
diff --git a/llvm/lib/Fuzzer/test/ExactTest.cpp b/llvm/lib/Fuzzer/test/ExactTest.cpp
index 662dd333eea4..c9898f3c811c 100644
--- a/llvm/lib/Fuzzer/test/ExactTest.cpp
+++ b/llvm/lib/Fuzzer/test/ExactTest.cpp
@@ -1,4 +1,5 @@
 // Simple test for a fuzzer. The fuzzer must find the string "FUZZER".
+#include <cstdint>
 #include <cstdlib>
 #include <cstddef>
 #include <iostream>
diff --git a/llvm/lib/Fuzzer/test/InfiniteTest.cpp b/llvm/lib/Fuzzer/test/InfiniteTest.cpp
index 9f4864abdd4c..ee1635d19968 100644
--- a/llvm/lib/Fuzzer/test/InfiniteTest.cpp
+++ b/llvm/lib/Fuzzer/test/InfiniteTest.cpp
@@ -1,4 +1,5 @@
 // Simple test for a fuzzer. The fuzzer must find the string "Hi!".
+#include <cstdint>
 #include <cstdlib>
 #include <cstddef>
 #include <iostream>
diff --git a/llvm/lib/Fuzzer/test/NullDerefTest.cpp b/llvm/lib/Fuzzer/test/NullDerefTest.cpp
index 602276f3c817..8811e386f9d3 100644
--- a/llvm/lib/Fuzzer/test/NullDerefTest.cpp
+++ b/llvm/lib/Fuzzer/test/NullDerefTest.cpp
@@ -1,4 +1,5 @@
 // Simple test for a fuzzer. The fuzzer must find the string "Hi!".
+#include <cstdint>
 #include <cstdlib>
 #include <cstddef>
 #include <iostream>
diff --git a/llvm/lib/Fuzzer/test/SimpleTest.cpp b/llvm/lib/Fuzzer/test/SimpleTest.cpp
index 9e20d8e6ac9c..adb90cebe86b 100644
--- a/llvm/lib/Fuzzer/test/SimpleTest.cpp
+++ b/llvm/lib/Fuzzer/test/SimpleTest.cpp
@@ -1,4 +1,5 @@
 // Simple test for a fuzzer. The fuzzer must find the string "Hi!".
+#include <cstdint>
 #include <cstdlib>
 #include <cstddef>
 #include <iostream>
diff --git a/llvm/lib/Fuzzer/test/TimeoutTest.cpp b/llvm/lib/Fuzzer/test/TimeoutTest.cpp
index c5a8ac00579b..266ead646a55 100644
--- a/llvm/lib/Fuzzer/test/TimeoutTest.cpp
+++ b/llvm/lib/Fuzzer/test/TimeoutTest.cpp
@@ -1,4 +1,5 @@
 // Simple test for a fuzzer. The fuzzer must find the string "Hi!".
+#include <cstdint>
 #include <cstdlib>
 #include <cstddef>
 #include <iostream>