Index: lib/profile/InstrProfilingUtil.h
===================================================================
--- lib/profile/InstrProfilingUtil.h
+++ lib/profile/InstrProfilingUtil.h
@@ -16,6 +16,12 @@
 /*! \brief Create a directory tree. */
 void __llvm_profile_recursive_mkdir(char *Pathname);
 
+/*! Set the mode used when creating profile directories. */
+void __llvm_profile_set_dir_mode(unsigned Mode);
+
+/*! Return the directory creation mode. */
+unsigned __llvm_profile_get_dir_mode(void);
+
 int lprofLockFd(int fd);
 int lprofUnlockFd(int fd);
 
Index: lib/profile/InstrProfilingUtil.c
===================================================================
--- lib/profile/InstrProfilingUtil.c
+++ lib/profile/InstrProfilingUtil.c
@@ -35,6 +35,8 @@
 #include "InstrProfiling.h"
 #include "InstrProfilingUtil.h"
 
+COMPILER_RT_WEAK unsigned lprofDirMode = 0755;
+
 COMPILER_RT_VISIBILITY
 void __llvm_profile_recursive_mkdir(char *path) {
   int i;
@@ -47,12 +49,19 @@
 #ifdef _WIN32
     _mkdir(path);
 #else
-    mkdir(path, 0755); /* Some of these will fail, ignore it. */
+    /* Some of these will fail, ignore it. */
+    mkdir(path, __llvm_profile_get_dir_mode());
 #endif
     path[i] = save;
   }
 }
 
+COMPILER_RT_VISIBILITY
+void __llvm_profile_set_dir_mode(unsigned Mode) { lprofDirMode = Mode; }
+
+COMPILER_RT_VISIBILITY
+unsigned __llvm_profile_get_dir_mode(void) { return lprofDirMode; }
+
 #if COMPILER_RT_HAS_ATOMICS != 1
 COMPILER_RT_VISIBILITY
 uint32_t lprofBoolCmpXchg(void **Ptr, void *OldV, void *NewV) {
Index: test/profile/instrprof-set-dir-mode.c
===================================================================
--- test/profile/instrprof-set-dir-mode.c
+++ test/profile/instrprof-set-dir-mode.c
@@ -0,0 +1,48 @@
+// UNSUPPORTED: windows
+// RUN: %clang_pgogen -o %t.bin %s -DTESTPATH=\"%t.dir\"
+// RUN: rm -rf %t.dir
+// RUN: %run %t.bin
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+
+void __llvm_profile_set_dir_mode(unsigned Mode);
+unsigned __llvm_profile_get_dir_mode(void);
+void __llvm_profile_recursive_mkdir(char *Path);
+
+static int test(unsigned Mode, const char *TestDir) {
+  int Ret = 0;
+
+  /* Create a dir and set the mode accordingly. */
+  char *Dir = strdup(TestDir);
+  if (!Dir)
+    return -1;
+  __llvm_profile_set_dir_mode(Mode);
+  __llvm_profile_recursive_mkdir(Dir);
+
+  if (Mode != __llvm_profile_get_dir_mode())
+    Ret = -1;
+  else {
+    const unsigned Expected = ~umask(0) & Mode;
+    struct stat DirSt;
+    if (stat(Dir, &DirSt) == -1)
+      Ret = -1;
+    else if (DirSt.st_mode != Expected) {
+      printf("Modes do not match: Expected %o but found %o (%s)\n", Expected,
+             DirSt.st_mode, Dir);
+      Ret = -1;
+    }
+  }
+
+  free(Dir);
+  return Ret;
+}
+
+int main(void) {
+  if (test(S_IFDIR | 0777, TESTPATH "/foo/bar/baz/") ||
+      test(S_IFDIR | 0666, TESTPATH "/foo/bar/qux/"))
+    return -1;
+  return 0;
+}