diff --git a/libc/bionic/c16rtomb.cpp b/libc/bionic/c16rtomb.cpp
index 2d6ae93..e052d04 100644
--- a/libc/bionic/c16rtomb.cpp
+++ b/libc/bionic/c16rtomb.cpp
@@ -43,7 +43,7 @@
 size_t c16rtomb(char* s, char16_t c16, mbstate_t* ps) {
   static mbstate_t __private_state;
   mbstate_t* state = (ps == nullptr) ? &__private_state : ps;
-  if (mbsinit(state)) {
+  if (mbstate_is_initial(state)) {
     if (is_high_surrogate(c16)) {
       char32_t c32 = (c16 & ~0xd800) << 10;
       mbstate_set_byte(state, 3, (c32 & 0xff0000) >> 16);
diff --git a/libc/bionic/c32rtomb.cpp b/libc/bionic/c32rtomb.cpp
index 2909d8b..d2519b9 100644
--- a/libc/bionic/c32rtomb.cpp
+++ b/libc/bionic/c32rtomb.cpp
@@ -50,7 +50,7 @@
     return mbstate_reset_and_return(1, state);
   }
 
-  if (!mbsinit(state)) {
+  if (!mbstate_is_initial(state)) {
     return mbstate_reset_and_return_illegal(EILSEQ, state);
   }
 
diff --git a/libc/bionic/mbrtoc32.cpp b/libc/bionic/mbrtoc32.cpp
index 644e542..21603a1 100644
--- a/libc/bionic/mbrtoc32.cpp
+++ b/libc/bionic/mbrtoc32.cpp
@@ -55,7 +55,7 @@
   }
 
   uint8_t ch;
-  if (mbsinit(state) && (((ch = static_cast<uint8_t>(*s)) & ~0x7f) == 0)) {
+  if (mbstate_is_initial(state) && (((ch = static_cast<uint8_t>(*s)) & ~0x7f) == 0)) {
     // Fast path for plain ASCII characters.
     if (pc32 != nullptr) {
       *pc32 = ch;
@@ -105,7 +105,7 @@
   size_t bytes_wanted = length - bytes_so_far;
   size_t i;
   for (i = 0; i < MIN(bytes_wanted, n); i++) {
-    if (!mbsinit(state) && ((*s & 0xc0) != 0x80)) {
+    if (!mbstate_is_initial(state) && ((*s & 0xc0) != 0x80)) {
       // Malformed input; bad characters in the middle of a character.
       return mbstate_reset_and_return_illegal(EILSEQ, state);
     }
diff --git a/libc/bionic/wchar.cpp b/libc/bionic/wchar.cpp
index dabe824..bd9a45e 100644
--- a/libc/bionic/wchar.cpp
+++ b/libc/bionic/wchar.cpp
@@ -54,7 +54,7 @@
 //
 
 int mbsinit(const mbstate_t* ps) {
-  return (ps == nullptr || (*(reinterpret_cast<const uint32_t*>(ps->__seq)) == 0));
+  return ps == nullptr || mbstate_is_initial(ps);
 }
 
 size_t mbrtowc(wchar_t* pwc, const char* s, size_t n, mbstate_t* ps) {
@@ -148,7 +148,7 @@
   static mbstate_t __private_state;
   mbstate_t* state = (ps == nullptr) ? &__private_state : ps;
 
-  if (!mbsinit(state)) {
+  if (!mbstate_is_initial(state)) {
     return mbstate_reset_and_return_illegal(EILSEQ, state);
   }
 
diff --git a/libc/private/bionic_mbstate.h b/libc/private/bionic_mbstate.h
index 352115a..243b220 100644
--- a/libc/private/bionic_mbstate.h
+++ b/libc/private/bionic_mbstate.h
@@ -44,6 +44,10 @@
 #define __MB_IS_ERR(rv) (rv == __MB_ERR_ILLEGAL_SEQUENCE || \
                          rv == __MB_ERR_INCOMPLETE_SEQUENCE)
 
+static inline __wur bool mbstate_is_initial(const mbstate_t* ps) {
+  return *(reinterpret_cast<const uint32_t*>(ps->__seq)) == 0;
+}
+
 static inline __wur size_t mbstate_bytes_so_far(const mbstate_t* ps) {
   return
       (ps->__seq[2] != 0) ? 3 :