Index: cmake/config-ix.cmake
===================================================================
--- cmake/config-ix.cmake
+++ cmake/config-ix.cmake
@@ -559,7 +559,7 @@
 endif()
 
 if (PROFILE_SUPPORTED_ARCH AND
-    OS_NAME MATCHES "Darwin|Linux|FreeBSD")
+    OS_NAME MATCHES "Darwin|Linux|FreeBSD|Windows")
   set(COMPILER_RT_HAS_PROFILE TRUE)
 else()
   set(COMPILER_RT_HAS_PROFILE FALSE)
Index: lib/profile/GCDAProfiling.c
===================================================================
--- lib/profile/GCDAProfiling.c
+++ lib/profile/GCDAProfiling.c
@@ -27,8 +27,13 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+
+#if defined(_WIN32)
+#include "mmap-windows.c"
+#else
 #include <sys/mman.h>
 #include <sys/file.h>
+#endif
 
 #define I386_FREEBSD (defined(__FreeBSD__) && defined(__i386__))
 
@@ -37,6 +42,7 @@
 #endif
 
 #if defined(_MSC_VER)
+typedef unsigned char uint8_t;
 typedef unsigned int uint32_t;
 typedef unsigned long long uint64_t;
 #elif I386_FREEBSD
Index: lib/profile/InstrProfilingFile.c
===================================================================
--- lib/profile/InstrProfilingFile.c
+++ lib/profile/InstrProfilingFile.c
@@ -17,6 +17,10 @@
 
 #define UNCONST(ptr) ((void *)(uintptr_t)(ptr))
 
+#ifdef _MSC_VER
+#define snprintf _snprintf
+#endif
+
 /* Return 1 if there is an error, otherwise return  0.  */
 static uint32_t fileWriter(ProfDataIOVec *IOVecs, uint32_t NumIOVecs,
                            void **WriterCtx) {
Index: lib/profile/mmap-windows.c
===================================================================
--- /dev/null
+++ lib/profile/mmap-windows.c
@@ -0,0 +1,153 @@
+/*
+ * This code is derived from uClibc (original license follows).
+ * https://git.uclibc.org/uClibc/tree/utils/mmap-windows.c
+ */
+ /* mmap() replacement for Windows
+ *
+ * Author: Mike Frysinger <vapier@gentoo.org>
+ * Placed into the public domain
+ */
+
+/* References:
+ * CreateFileMapping: http://msdn.microsoft.com/en-us/library/aa366537(VS.85).aspx
+ * CloseHandle:       http://msdn.microsoft.com/en-us/library/ms724211(VS.85).aspx
+ * MapViewOfFile:     http://msdn.microsoft.com/en-us/library/aa366761(VS.85).aspx
+ * UnmapViewOfFile:   http://msdn.microsoft.com/en-us/library/aa366882(VS.85).aspx
+ */
+
+#include <io.h>
+#include <windows.h>
+#include <sys/types.h>
+
+#define PROT_READ     0x1
+#define PROT_WRITE    0x2
+/* This flag is only available in WinXP+ */
+#ifdef FILE_MAP_EXECUTE
+#define PROT_EXEC     0x4
+#else
+#define PROT_EXEC        0x0
+#define FILE_MAP_EXECUTE 0
+#endif
+
+#define MAP_FILE      0x00
+#define MAP_SHARED    0x01
+#define MAP_PRIVATE   0x02
+#define MAP_ANONYMOUS 0x20
+#define MAP_ANON      MAP_ANONYMOUS
+#define MAP_FAILED    ((void *) -1)
+
+#ifdef __USE_FILE_OFFSET64
+# define DWORD_HI(x) (x >> 32)
+# define DWORD_LO(x) ((x) & 0xffffffff)
+#else
+# define DWORD_HI(x) (0)
+# define DWORD_LO(x) (x)
+#endif
+
+/*
+ * msync() flags
+ */
+#define MS_ASYNC        0x0001  /* return immediately */
+#define MS_INVALIDATE   0x0002  /* invalidate all cached data */
+#define MS_SYNC         0x0010  /* msync synchronously */
+
+/*
+ * flock() operations
+ */
+#define   LOCK_SH   1    /* shared lock */
+#define   LOCK_EX   2    /* exclusive lock */
+#define   LOCK_NB   4    /* don't block when locking */
+#define   LOCK_UN   8    /* unlock */
+
+static void *mmap(void *start, size_t length, int prot, int flags, int fd, off_t offset)
+{
+  if (prot & ~(PROT_READ | PROT_WRITE | PROT_EXEC))
+    return MAP_FAILED;
+  if (fd == -1) {
+    if (!(flags & MAP_ANON) || offset)
+      return MAP_FAILED;
+  } else if (flags & MAP_ANON)
+    return MAP_FAILED;
+
+  DWORD flProtect;
+  if (prot & PROT_WRITE) {
+    if (prot & PROT_EXEC)
+      flProtect = PAGE_EXECUTE_READWRITE;
+    else
+      flProtect = PAGE_READWRITE;
+  } else if (prot & PROT_EXEC) {
+    if (prot & PROT_READ)
+      flProtect = PAGE_EXECUTE_READ;
+    else if (prot & PROT_EXEC)
+      flProtect = PAGE_EXECUTE;
+  } else
+    flProtect = PAGE_READONLY;
+
+  off_t end = length + offset;
+  HANDLE mmap_fd, h;
+  if (fd == -1)
+    mmap_fd = INVALID_HANDLE_VALUE;
+  else
+    mmap_fd = (HANDLE)_get_osfhandle(fd);
+  h = CreateFileMapping(mmap_fd, NULL, flProtect, DWORD_HI(end), DWORD_LO(end), NULL);
+  if (h == NULL)
+    return MAP_FAILED;
+
+  DWORD dwDesiredAccess;
+  if (prot & PROT_WRITE)
+    dwDesiredAccess = FILE_MAP_WRITE;
+  else
+    dwDesiredAccess = FILE_MAP_READ;
+  if (prot & PROT_EXEC)
+    dwDesiredAccess |= FILE_MAP_EXECUTE;
+  if (flags & MAP_PRIVATE)
+    dwDesiredAccess |= FILE_MAP_COPY;
+  void *ret = MapViewOfFile(h, dwDesiredAccess, DWORD_HI(offset), DWORD_LO(offset), length);
+  if (ret == NULL) {
+    CloseHandle(h);
+    ret = MAP_FAILED;
+  }
+  return ret;
+}
+
+static void munmap(void *addr, size_t length)
+{
+  UnmapViewOfFile(addr);
+  /* ruh-ro, we leaked handle from CreateFileMapping() ... */
+}
+
+static int msync(void *addr, size_t length, int flags)
+{
+  if (flags & MS_INVALIDATE)
+    return -1; /* Not supported. */
+
+  /* Exactly one of MS_ASYNC or MS_SYNC must be specified. */
+  switch (flags & (MS_ASYNC | MS_SYNC)) {
+    case MS_SYNC:
+    case MS_ASYNC:
+      break;
+    default:
+      return -1;
+  }
+
+  if (!FlushViewOfFile(addr, length))
+    return -1;
+
+  if (flags & MS_SYNC) {
+    /* FIXME: No longer have access to handle from CreateFileMapping(). */
+    /*
+     * if (!FlushFileBuffers(h))
+     *   return -1;
+     */
+  }
+
+  return 0;
+}
+
+static int flock(int fd, int operation)
+{
+  return -1; /* Not supported. */
+}
+
+#undef DWORD_HI
+#undef DWORD_LO