diff --git a/src/header/string/mod.rs b/src/header/string/mod.rs
index 92bf959ab682604d91ac083643d7137d39bdf18a..444fd8c61fd80d5f0d07506e119e32110cfd5206 100644
--- a/src/header/string/mod.rs
+++ b/src/header/string/mod.rs
@@ -139,10 +139,8 @@ pub unsafe extern "C" fn memmove(s1: *mut c_void, s2: *const c_void, n: size_t)
 
 #[no_mangle]
 pub unsafe extern "C" fn memset(s: *mut c_void, c: c_int, n: size_t) -> *mut c_void {
-    let mut i = 0;
-    while i < n {
+    for i in 0..n {
         *(s as *mut u8).add(i) = c as u8;
-        i += 1;
     }
     s
 }
@@ -235,10 +233,8 @@ pub unsafe extern "C" fn strndup(s1: *const c_char, size: size_t) -> *mut c_char
         platform::errno = ENOMEM as c_int;
     } else {
         //memcpy(buffer, s1, len)
-        let mut i = 0;
-        while i < len {
+        for i in 0..len {
             *buffer.add(i) = *s1.add(i);
-            i += 1;
         }
         *buffer.add(len) = 0;
     }
diff --git a/src/header/wchar/mod.rs b/src/header/wchar/mod.rs
index 00fc9365a1030905b600849e3a1d9cd8441621d5..5d496529304242458c5d6d7ebf1126ff586e5c6a 100644
--- a/src/header/wchar/mod.rs
+++ b/src/header/wchar/mod.rs
@@ -389,8 +389,7 @@ pub unsafe extern "C" fn wcsncat(
 
 #[no_mangle]
 pub unsafe extern "C" fn wcsncmp(ws1: *const wchar_t, ws2: *const wchar_t, n: size_t) -> c_int {
-    let mut i = 0;
-    while i < n {
+    for i in 0..n {
         let wc1 = *ws1.add(i);
         let wc2 = *ws2.add(i);
         if wc1 != wc2 {
@@ -398,7 +397,6 @@ pub unsafe extern "C" fn wcsncmp(ws1: *const wchar_t, ws2: *const wchar_t, n: si
         } else if wc1 == 0 {
             break;
         }
-        i += 1;
     }
     0
 }
@@ -520,26 +518,22 @@ pub extern "C" fn wcwidth(wc: wchar_t) -> c_int {
 
 #[no_mangle]
 pub unsafe extern "C" fn wmemchr(ws: *const wchar_t, wc: wchar_t, n: size_t) -> *mut wchar_t {
-    let mut i = 0;
-    while i < n {
+    for i in 0..n {
         if *ws.add(i) == wc {
             return ws.add(i) as *mut wchar_t;
         }
-        i += 1;
     }
     0 as *mut wchar_t
 }
 
 #[no_mangle]
 pub unsafe extern "C" fn wmemcmp(ws1: *const wchar_t, ws2: *const wchar_t, n: size_t) -> c_int {
-    let mut i = 0;
-    while i < n {
+    for i in 0..n {
         let wc1 = *ws1.add(i);
         let wc2 = *ws2.add(i);
         if wc1 != wc2 {
             return wc1 - wc2;
         }
-        i += 1;
     }
     0
 }
@@ -572,10 +566,8 @@ pub unsafe extern "C" fn wmemmove(
 
 #[no_mangle]
 pub unsafe extern "C" fn wmemset(ws: *mut wchar_t, wc: wchar_t, n: size_t) -> *mut wchar_t {
-    let mut i = 0;
-    while i < n {
+    for i in 0..n {
         *ws.add(i) = wc;
-        i += 1;
     }
     ws
 }