diff --git a/libc/stdio/vfscanf.cpp b/libc/stdio/vfscanf.cpp
index dfd001d..65f54a5 100644
--- a/libc/stdio/vfscanf.cpp
+++ b/libc/stdio/vfscanf.cpp
@@ -31,53 +31,7 @@
  * SUCH DAMAGE.
  */
 
-#include <ctype.h>
-#include <inttypes.h>
-#include <stdarg.h>
-#include <stddef.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/param.h>
-#include <wctype.h>
-#include "local.h"
-
-#include <private/bionic_fortify.h>
-#include <platform/bionic/macros.h>
-#include <private/bionic_mbstate.h>
-
-#define BUF 513 /* Maximum length of numeric string. */
-
-// Flags used during conversion.
-// Size/type:
-#define LONG       0x00001 // l: long or double
-#define LONGDBL    0x00002 // L: long double
-#define SHORT      0x00004 // h: short
-#define SHORTSHORT 0x00008 // hh: 8 bit integer
-#define LLONG      0x00010 // ll: long long (+ deprecated q: quad)
-#define POINTER    0x00020 // p: void* (as hex)
-#define SIZEINT    0x00040 // z: (signed) size_t
-#define MAXINT     0x00080 // j: intmax_t
-#define PTRINT     0x00100 // t: ptrdiff_t
-#define NOSKIP     0x00200 // [ or c: do not skip blanks
-// Modifiers:
-#define SUPPRESS   0x00400 // *: suppress assignment
-#define UNSIGNED   0x00800 // %[oupxX] conversions
-#define ALLOCATE   0x01000 // m: allocate a char*
-// Internal use during integer parsing:
-#define SIGNOK     0x02000 // +/- is (still) legal
-#define HAVESIGN   0x04000 // Sign detected
-#define NDIGITS    0x08000 // No digits detected
-#define PFXOK      0x10000 // "0x" prefix is (still) legal
-#define PFBOK      0x20000 // "0b" prefix is (still) legal
-#define NZDIGITS   0x40000 // No zero digits detected
-
-// Conversion types.
-#define CT_CHAR 0   // %c conversion
-#define CT_CCL 1    // %[...] conversion
-#define CT_STRING 2 // %s conversion
-#define CT_INT 3    // Integer: strtoimax/strtoumax
-#define CT_FLOAT 4  // Float: strtod
+#include "scanf_common.h"
 
 static const unsigned char* __sccl(char*, const unsigned char*);
 
@@ -122,6 +76,7 @@
      */
 again:
     c = *fmt++;
+reswitch:
     switch (c) {
       case '%':
 literal:
@@ -220,6 +175,18 @@
         base = 10;
         break;
 
+      case 'w': {
+        int size = 0;
+        bool fast = false;
+        c = *fmt++;
+        while (is_digit(c)) {
+          APPEND_DIGIT(size, c);
+          c = *fmt++;
+        }
+        flags |= w_to_flag(size, fast);
+        goto reswitch;
+      }
+
       case 'X':
       case 'x':
         flags |= PFXOK; /* enable 0x prefixing */