Index: compiler-rt/include/sanitizer/msan_interface.h
===================================================================
--- compiler-rt/include/sanitizer/msan_interface.h
+++ compiler-rt/include/sanitizer/msan_interface.h
@@ -104,6 +104,14 @@
      copy. Source and destination regions can overlap. */
   void __msan_copy_shadow(const volatile void *dst, const volatile void *src,
                           size_t size);
+
+  /* Disables uninitialized memory checks in interceptors. */
+  void __msan_disable_interceptor_checks(void);
+
+  /* Re-enables uninitialized memory checks in interceptors after a previous
+     call to __msan_disable_interceptor_checks. */
+  void __msan_reenable_interceptor_checks(void);
+
 #ifdef __cplusplus
 }  // extern "C"
 #endif
Index: compiler-rt/lib/msan/msan_interceptors.cc
===================================================================
--- compiler-rt/lib/msan/msan_interceptors.cc
+++ compiler-rt/lib/msan/msan_interceptors.cc
@@ -60,6 +60,9 @@
 // True if this is a nested interceptor.
 static THREADLOCAL int in_interceptor_scope;
 
+void __msan_disable_interceptor_checks() { ++in_interceptor_scope; }
+void __msan_reenable_interceptor_checks() { --in_interceptor_scope; }
+
 struct InterceptorScope {
   InterceptorScope() { ++in_interceptor_scope; }
   ~InterceptorScope() { --in_interceptor_scope; }
Index: compiler-rt/lib/msan/msan_interface_internal.h
===================================================================
--- compiler-rt/lib/msan/msan_interface_internal.h
+++ compiler-rt/lib/msan/msan_interface_internal.h
@@ -174,6 +174,12 @@
 
 SANITIZER_INTERFACE_ATTRIBUTE
 void __msan_copy_shadow(void *dst, const void *src, uptr size);
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_disable_interceptor_checks();
+
+SANITIZER_INTERFACE_ATTRIBUTE
+void __msan_reenable_interceptor_checks();
 }  // extern "C"
 
 #endif  // MSAN_INTERFACE_INTERNAL_H