Index: lib/profile/InstrProfilingFile.c
===================================================================
--- lib/profile/InstrProfilingFile.c
+++ lib/profile/InstrProfilingFile.c
@@ -300,18 +300,18 @@
       if (FilenamePat[++I] == 'p') {
         if (!NumPids++) {
           if (snprintf(PidChars, MAX_PID_SIZE, "%d", getpid()) <= 0) {
-            PROF_WARN(
-                "Unable to parse filename pattern %s. Using the default name.",
-                FilenamePat);
+            PROF_WARN("Unable to get pid for filename pattern %s. Using the "
+                      "default name.",
+                      FilenamePat);
             return -1;
           }
         }
       } else if (FilenamePat[I] == 'h') {
         if (!NumHosts++)
           if (COMPILER_RT_GETHOSTNAME(Hostname, COMPILER_RT_MAX_HOSTLEN)) {
-            PROF_WARN(
-                "Unable to parse filename pattern %s. Using the default name.",
-                FilenamePat);
+            PROF_WARN("Unable to get hostname for filename pattern %s. Using "
+                      "the default name.",
+                      FilenamePat);
             return -1;
           }
       } else if (containsMergeSpecifier(FilenamePat, I)) {
Index: lib/profile/InstrProfilingPort.h
===================================================================
--- lib/profile/InstrProfilingPort.h
+++ lib/profile/InstrProfilingPort.h
@@ -40,14 +40,14 @@
 #endif
 
 #define COMPILER_RT_MAX_HOSTLEN 128
-#ifdef _MSC_VER
-#define COMPILER_RT_GETHOSTNAME(Name, Len) gethostname(Name, Len)
-#elif defined(__ORBIS__)
+#ifdef __ORBIS__
 #define COMPILER_RT_GETHOSTNAME(Name, Len) ((void)(Name), (void)(Len), (-1))
 #else
 #define COMPILER_RT_GETHOSTNAME(Name, Len) lprofGetHostName(Name, Len)
+#ifndef _MSC_VER
 #define COMPILER_RT_HAS_UNAME 1
 #endif
+#endif
 
 #if COMPILER_RT_HAS_ATOMICS == 1
 #ifdef _MSC_VER
Index: lib/profile/InstrProfilingUtil.c
===================================================================
--- lib/profile/InstrProfilingUtil.c
+++ lib/profile/InstrProfilingUtil.c
@@ -66,7 +66,19 @@
 
 #endif
 
-#ifdef COMPILER_RT_HAS_UNAME
+#ifdef _MSC_VER
+COMPILER_RT_VISIBILITY int lprofGetHostName(char *Name, int Len) {
+  WCHAR Buffer[COMPILER_RT_MAX_HOSTLEN];
+  DWORD BufferSize = sizeof(Buffer);
+  BOOL Result =
+      GetComputerNameExW(ComputerNameDnsFullyQualified, Buffer, &BufferSize);
+  if (!Result)
+    return -1;
+  if (WideCharToMultiByte(CP_UTF8, 0, Buffer, -1, Name, Len, NULL, NULL) == 0)
+    return -1;
+  return 0;
+}
+#elif defined(COMPILER_RT_HAS_UNAME)
 COMPILER_RT_VISIBILITY int lprofGetHostName(char *Name, int Len) {
   struct utsname N;
   int R;