diff --git a/src/Makefile.am b/src/Makefile.am
index a3d47ce..78af0a9 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -63,9 +63,6 @@ endif
 if USE_SSL_NSS
     s3fs_SOURCES += nss_auth.cpp
 endif
-if MSYS
-    s3fs_SOURCES += strptime.cpp
-endif
 
 s3fs_LDADD = $(DEPS_LIBS)
 
@@ -84,9 +81,6 @@ endif
 if USE_SSL_NSS
     test_curl_util_SOURCES += nss_auth.cpp
 endif
-if MSYS
-    test_curl_util_SOURCES += strptime.cpp
-endif
 
 test_curl_util_LDADD = $(DEPS_LIBS)
 
@@ -96,14 +90,8 @@ test_page_list_SOURCES = \
     s3fs_logger.cpp \
     string_util.cpp \
     test_page_list.cpp
-if MSYS
-    test_page_list_SOURCES += strptime.cpp
-endif
 
 test_string_util_SOURCES = string_util.cpp test_string_util.cpp s3fs_logger.cpp
-if MSYS
-    test_string_util_SOURCES += strptime.cpp
-endif
 
 TESTS = \
     test_curl_util \
diff --git a/src/metaheader.cpp b/src/metaheader.cpp
index bdf533a..19b236c 100644
--- a/src/metaheader.cpp
+++ b/src/metaheader.cpp
@@ -28,11 +28,6 @@
 #include "metaheader.h"
 #include "string_util.h"
 
-// Use the polyfill in MSYS2 environment
-#ifdef __MSYS__
-#include "strptime.h"
-#endif
-
 //-------------------------------------------------------------------
 // Utility functions for convert
 //-------------------------------------------------------------------
diff --git a/src/string_util.cpp b/src/string_util.cpp
index 9bb674b..b0e4d6c 100644
--- a/src/string_util.cpp
+++ b/src/string_util.cpp
@@ -32,11 +32,6 @@
 #include "s3fs.h"
 #include "string_util.h"
 
-// Use the polyfill in MSYS2 environment
-#ifdef __MSYS__
-#include "strptime.h"
-#endif
-
 //-------------------------------------------------------------------
 // Global variables
 //-------------------------------------------------------------------
@@ -74,6 +69,24 @@ template<> std::string str(struct timespec value) {
 // Functions
 //-------------------------------------------------------------------
 
+#ifdef __MSYS__
+/*
+ * Polyfill for strptime function
+ *
+ * This source code is from https://gist.github.com/jeremyfromearth/5694aa3a66714254752179ecf3c95582 .
+ */
+char* strptime(const char* s, const char* f, struct tm* tm)
+{
+    std::istringstream input(s);
+    input.imbue(std::locale(setlocale(LC_ALL, nullptr)));
+    input >> std::get_time(tm, f);
+    if (input.fail()) {
+        return nullptr;
+    }
+    return (char*)(s + input.tellg());
+}
+#endif
+
 bool s3fs_strtoofft(off_t* value, const char* str, int base)
 {
     if(value == NULL || str == NULL){
diff --git a/src/string_util.h b/src/string_util.h
index e5c857e..54c629a 100644
--- a/src/string_util.h
+++ b/src/string_util.h
@@ -54,6 +54,12 @@ template <class T> std::string str(T value);
 //-------------------------------------------------------------------
 // Utilities
 //-------------------------------------------------------------------
+#ifdef __MSYS__
+//
+// Polyfill for strptime function.
+//
+char* strptime(const char* s, const char* f, struct tm* tm);
+#endif
 //
 // Convert string to off_t.  Returns false on bad input.
 // Replacement for C++11 std::stoll.
diff --git a/src/strptime.cpp b/src/strptime.cpp
deleted file mode 100644
index e923ee4..0000000
--- a/src/strptime.cpp
+++ /dev/null
@@ -1,23 +0,0 @@
-/*
- * Polyfill for strptime function
- *
- * This source code is from https://gist.github.com/jeremyfromearth/5694aa3a66714254752179ecf3c95582 .
- */
-
-#include <iostream>
-#include <time.h>
-#include <iomanip>
-#include <sstream>
-
-#include "strptime.h"
-
-char* strptime(const char* s, const char* f, struct tm* tm)
-{
-    std::istringstream input(s);
-    input.imbue(std::locale(setlocale(LC_ALL, nullptr)));
-    input >> std::get_time(tm, f);
-    if (input.fail()) {
-        return nullptr;
-    }
-    return (char*)(s + input.tellg());
-}
diff --git a/src/strptime.h b/src/strptime.h
deleted file mode 100644
index 1ca97db..0000000
--- a/src/strptime.h
+++ /dev/null
@@ -1,50 +0,0 @@
-
-/*
- * Polyfill for strptime function
- *
- * This source code is from musl library, located at https://git.musl-libc.org/cgit/musl/tree/src/time/strptime.c .
- */
-
-/*
- * musl as a whole is licensed under the following standard MIT license:
- * 
- * ----------------------------------------------------------------------
- * Copyright © 2005-2020 Rich Felker, et al.
- * 
- * Permission is hereby granted, free of charge, to any person obtaining
- * a copy of this software and associated documentation files (the
- * "Software"), to deal in the Software without restriction, including
- * without limitation the rights to use, copy, modify, merge, publish,
- * distribute, sublicense, and/or sell copies of the Software, and to
- * permit persons to whom the Software is furnished to do so, subject to
- * the following conditions:
- * 
- * The above copyright notice and this permission notice shall be
- * included in all copies or substantial portions of the Software.
- * 
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
- * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
- * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
- * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
- * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- * ----------------------------------------------------------------------
- */
-
-#ifndef S3FS_STRPTIME_H_
-#define S3FS_STRPTIME_H_
-
-#include <stdlib.h>
-#include <langinfo.h>
-#include <time.h>
-#include <ctype.h>
-#include <stddef.h>
-#include <string.h>
-#include <strings.h>
-
-#include "common.h"
-
-char* strptime(const char* s, const char* f, struct tm* tm);
-
-#endif