Index: lib/asan/asan_interface_internal.h
===================================================================
--- lib/asan/asan_interface_internal.h
+++ lib/asan/asan_interface_internal.h
@@ -23,6 +23,8 @@
 #include "asan_init_version.h"
 
 using __sanitizer::uptr;
+using __sanitizer::u64;
+using __sanitizer::u32;
 
 extern "C" {
   // This function should be called at the very beginning of the process,
Index: lib/asan/tests/asan_noinst_test.cc
===================================================================
--- lib/asan/tests/asan_noinst_test.cc
+++ lib/asan/tests/asan_noinst_test.cc
@@ -26,6 +26,8 @@
 #include <vector>
 #include <limits>
 
+using namespace __sanitizer;
+
 // ATTENTION!
 // Please don't call intercepted functions (including malloc() and friends)
 // in this test. The static runtime library is linked explicitly (without
Index: lib/cfi/cfi.cc
===================================================================
--- lib/cfi/cfi.cc
+++ lib/cfi/cfi.cc
@@ -30,6 +30,8 @@
 #include "ubsan/ubsan_handlers.h"
 #endif
 
+using namespace __sanitizer;
+
 namespace __cfi {
 
 #define kCfiShadowLimitsStorageSize 4096 // 1 page
Index: lib/dfsan/dfsan.h
===================================================================
--- lib/dfsan/dfsan.h
+++ lib/dfsan/dfsan.h
@@ -18,6 +18,9 @@
 #include "sanitizer_common/sanitizer_internal_defs.h"
 #include "dfsan_platform.h"
 
+using __sanitizer::uptr;
+using __sanitizer::u16;
+
 // Copy declarations from public sanitizer/dfsan_interface.h header here.
 typedef u16 dfsan_label;
 
Index: lib/dfsan/dfsan_interceptors.cc
===================================================================
--- lib/dfsan/dfsan_interceptors.cc
+++ lib/dfsan/dfsan_interceptors.cc
@@ -16,6 +16,8 @@
 #include "interception/interception.h"
 #include "sanitizer_common/sanitizer_common.h"
 
+using namespace __sanitizer;
+
 INTERCEPTOR(void *, mmap, void *addr, SIZE_T length, int prot, int flags,
             int fd, OFF_T offset) {
   void *res = REAL(mmap)(addr, length, prot, flags, fd, offset);
Index: lib/esan/esan_flags.cpp
===================================================================
--- lib/esan/esan_flags.cpp
+++ lib/esan/esan_flags.cpp
@@ -17,6 +17,8 @@
 #include "sanitizer_common/sanitizer_flag_parser.h"
 #include "sanitizer_common/sanitizer_flags.h"
 
+using namespace __sanitizer;
+
 namespace __esan {
 
 static const char EsanOptsEnv[] = "ESAN_OPTIONS";
Index: lib/esan/esan_interface_internal.h
===================================================================
--- lib/esan/esan_interface_internal.h
+++ lib/esan/esan_interface_internal.h
@@ -21,6 +21,9 @@
 // This header should NOT include any other headers.
 // All functions in this header are extern "C" and start with __esan_.
 
+using __sanitizer::uptr;
+using __sanitizer::u32;
+
 extern "C" {
 
 // This should be kept consistent with LLVM's EfficiencySanitizerOptions.
Index: lib/interception/interception.h
===================================================================
--- lib/interception/interception.h
+++ lib/interception/interception.h
@@ -92,8 +92,8 @@
 
 // Just a pair of pointers.
 struct interpose_substitution {
-  const uptr replacement;
-  const uptr original;
+  const __sanitizer::uptr replacement;
+  const __sanitizer::uptr original;
 };
 
 // For a function foo() create a global pair of pointers { wrap_foo, foo } in
Index: lib/msan/msan_interface_internal.h
===================================================================
--- lib/msan/msan_interface_internal.h
+++ lib/msan/msan_interface_internal.h
@@ -37,6 +37,16 @@
 SANITIZER_INTERFACE_ATTRIBUTE __attribute__((noreturn))
 void __msan_warning_noreturn();
 
+using __sanitizer::uptr;
+using __sanitizer::sptr;
+using __sanitizer::uu64;
+using __sanitizer::uu32;
+using __sanitizer::uu16;
+using __sanitizer::u64;
+using __sanitizer::u32;
+using __sanitizer::u16;
+using __sanitizer::u8;
+
 SANITIZER_INTERFACE_ATTRIBUTE
 void __msan_maybe_warning_1(u8 s, u32 o);
 SANITIZER_INTERFACE_ATTRIBUTE
Index: lib/safestack/safestack.cc
===================================================================
--- lib/safestack/safestack.cc
+++ lib/safestack/safestack.cc
@@ -92,6 +92,8 @@
 static __thread size_t unsafe_stack_size = 0;
 static __thread size_t unsafe_stack_guard = 0;
 
+using namespace __sanitizer;
+
 static inline void *unsafe_stack_alloc(size_t size, size_t guard) {
   CHECK_GE(size + guard, size);
   void *addr = MmapOrDie(size + guard, "unsafe_stack_alloc");
Index: lib/sanitizer_common/sanitizer_allocator_internal.h
===================================================================
--- lib/sanitizer_common/sanitizer_allocator_internal.h
+++ lib/sanitizer_common/sanitizer_allocator_internal.h
@@ -61,8 +61,8 @@
 } // namespace __sanitizer
 
 inline void *operator new(__sanitizer::operator_new_size_type size,
-                          InternalAllocEnum) {
-  return InternalAlloc(size);
+                          __sanitizer::InternalAllocEnum) {
+  return __sanitizer::InternalAlloc(size);
 }
 
 #endif // SANITIZER_ALLOCATOR_INTERNAL_H
Index: lib/sanitizer_common/sanitizer_common.h
===================================================================
--- lib/sanitizer_common/sanitizer_common.h
+++ lib/sanitizer_common/sanitizer_common.h
@@ -827,6 +827,11 @@
 INLINE void AvoidCVE_2016_2143() {}
 #endif
 
+struct StackDepotStats {
+  uptr n_uniq_ids;
+  uptr allocated;
+};
+
 }  // namespace __sanitizer
 
 inline void *operator new(__sanitizer::operator_new_size_type size,
@@ -834,9 +839,4 @@
   return alloc.Allocate(size);
 }
 
-struct StackDepotStats {
-  uptr n_uniq_ids;
-  uptr allocated;
-};
-
 #endif  // SANITIZER_COMMON_H
Index: lib/sanitizer_common/sanitizer_common_libcdep.cc
===================================================================
--- lib/sanitizer_common/sanitizer_common_libcdep.cc
+++ lib/sanitizer_common/sanitizer_common_libcdep.cc
@@ -152,7 +152,7 @@
 
 void NOINLINE
 __sanitizer_sandbox_on_notify(__sanitizer_sandbox_arguments *args) {
-  PrepareForSandboxing(args);
-  if (sandboxing_callback)
-    sandboxing_callback();
+  __sanitizer::PrepareForSandboxing(args);
+  if (__sanitizer::sandboxing_callback)
+    __sanitizer::sandboxing_callback();
 }
Index: lib/sanitizer_common/sanitizer_coverage_libcdep.cc
===================================================================
--- lib/sanitizer_common/sanitizer_coverage_libcdep.cc
+++ lib/sanitizer_common/sanitizer_coverage_libcdep.cc
@@ -47,6 +47,8 @@
 #include "sanitizer_symbolizer.h"
 #include "sanitizer_flags.h"
 
+using namespace __sanitizer;
+
 static const u64 kMagic64 = 0xC0BFFFFFFFFFFF64ULL;
 static const u64 kMagic32 = 0xC0BFFFFFFFFFFF32ULL;
 static const uptr kNumWordsForMagic = SANITIZER_WORDSIZE == 64 ? 1 : 2;
Index: lib/sanitizer_common/sanitizer_internal_defs.h
===================================================================
--- lib/sanitizer_common/sanitizer_internal_defs.h
+++ lib/sanitizer_common/sanitizer_internal_defs.h
@@ -328,6 +328,17 @@
 
 }  // namespace __sanitizer
 
-using namespace __sanitizer;  // NOLINT
+namespace __asan  { using namespace __sanitizer; }  // NOLINT
+namespace __dsan  { using namespace __sanitizer; }  // NOLINT
+namespace __dfsan { using namespace __sanitizer; }  // NOLINT
+namespace __esan  { using namespace __sanitizer; }  // NOLINT
+namespace __lsan  { using namespace __sanitizer; }  // NOLINT
+namespace __msan  { using namespace __sanitizer; }  // NOLINT
+namespace __tsan  { using namespace __sanitizer; }  // NOLINT
+namespace __scudo { using namespace __sanitizer; }  // NOLINT
+namespace __ubsan { using namespace __sanitizer; }  // NOLINT
+namespace __xray  { using namespace __sanitizer; }  // NOLINT
+namespace __interception  { using namespace __sanitizer; }  // NOLINT
+
 
 #endif  // SANITIZER_DEFS_H
Index: lib/sanitizer_common/sanitizer_mac.h
===================================================================
--- lib/sanitizer_common/sanitizer_mac.h
+++ lib/sanitizer_common/sanitizer_mac.h
@@ -39,17 +39,21 @@
 }  // namespace __sanitizer
 
 extern "C" {
-static char __crashreporter_info_buff__[kErrorMessageBufferSize] = {};
+static char __crashreporter_info_buff__[__sanitizer::kErrorMessageBufferSize] =
+  {};
 static const char *__crashreporter_info__ __attribute__((__used__)) =
   &__crashreporter_info_buff__[0];
 asm(".desc ___crashreporter_info__, 0x10");
 } // extern "C"
+
+namespace __sanitizer {
 static BlockingMutex crashreporter_info_mutex(LINKER_INITIALIZED);
 
 INLINE void CRAppendCrashLogMessage(const char *msg) {
   BlockingMutexLock l(&crashreporter_info_mutex);
   internal_strlcat(__crashreporter_info_buff__, msg,
                    sizeof(__crashreporter_info_buff__)); }
+}  // namespace __sanitizer
 
 #endif  // SANITIZER_MAC
 #endif  // SANITIZER_MAC_H
Index: lib/sanitizer_common/sanitizer_platform_limits_linux.cc
===================================================================
--- lib/sanitizer_common/sanitizer_platform_limits_linux.cc
+++ lib/sanitizer_common/sanitizer_platform_limits_linux.cc
@@ -55,6 +55,8 @@
 #include <linux/perf_event.h>
 #endif
 
+using namespace __sanitizer;
+
 namespace __sanitizer {
 #if !SANITIZER_ANDROID
   unsigned struct_statfs64_sz = sizeof(struct statfs64);
Index: lib/sanitizer_common/sanitizer_platform_limits_posix.cc
===================================================================
--- lib/sanitizer_common/sanitizer_platform_limits_posix.cc
+++ lib/sanitizer_common/sanitizer_platform_limits_posix.cc
@@ -937,6 +937,8 @@
   const int si_SEGV_ACCERR = SEGV_ACCERR;
 } // namespace __sanitizer
 
+using namespace __sanitizer;
+
 COMPILER_CHECK(sizeof(__sanitizer_pthread_attr_t) >= sizeof(pthread_attr_t));
 
 COMPILER_CHECK(sizeof(socklen_t) == sizeof(unsigned));
Index: lib/sanitizer_common/sanitizer_stacktrace_libcdep.cc
===================================================================
--- lib/sanitizer_common/sanitizer_stacktrace_libcdep.cc
+++ lib/sanitizer_common/sanitizer_stacktrace_libcdep.cc
@@ -86,8 +86,9 @@
 
 extern "C" {
 SANITIZER_INTERFACE_ATTRIBUTE
-void __sanitizer_symbolize_pc(uptr pc, const char *fmt, char *out_buf,
-                              uptr out_buf_size) {
+void __sanitizer_symbolize_pc(__sanitizer::uptr pc,
+                              const char *fmt, char *out_buf,
+                              __sanitizer::uptr out_buf_size) {
   using namespace __sanitizer;
   pc = StackTrace::GetPreviousInstructionPc(pc);
   SymbolizedStack *frame = Symbolizer::GetOrInit()->SymbolizePC(pc);
Index: lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc
===================================================================
--- lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc
+++ lib/sanitizer_common/sanitizer_stoptheworld_linux_libcdep.cc
@@ -79,10 +79,10 @@
 // thread-local variables used by libc will be shared between the tracer task
 // and the thread which spawned it.
 
-COMPILER_CHECK(sizeof(SuspendedThreadID) == sizeof(pid_t));
-
 namespace __sanitizer {
 
+COMPILER_CHECK(sizeof(SuspendedThreadID) == sizeof(pid_t));
+
 // Structure for passing arguments into the tracer thread.
 struct TracerThreadArgument {
   StopTheWorldCallback callback;
Index: lib/sanitizer_common/tests/sanitizer_allocator_test.cc
===================================================================
--- lib/sanitizer_common/tests/sanitizer_allocator_test.cc
+++ lib/sanitizer_common/tests/sanitizer_allocator_test.cc
@@ -25,6 +25,8 @@
 #include <vector>
 #include <set>
 
+using namespace __sanitizer;
+
 // Too slow for debug build
 #if !SANITIZER_DEBUG
 
Index: lib/sanitizer_common/tests/sanitizer_libc_test.cc
===================================================================
--- lib/sanitizer_common/tests/sanitizer_libc_test.cc
+++ lib/sanitizer_common/tests/sanitizer_libc_test.cc
@@ -25,6 +25,8 @@
 # include "sanitizer_common/sanitizer_posix.h"
 #endif
 
+using namespace __sanitizer;
+
 // A regression test for internal_memmove() implementation.
 TEST(SanitizerCommon, InternalMemmoveRegression) {
   char src[] = "Hello World";
Index: lib/sanitizer_common/tests/sanitizer_nolibc_test_main.cc
===================================================================
--- lib/sanitizer_common/tests/sanitizer_nolibc_test_main.cc
+++ lib/sanitizer_common/tests/sanitizer_nolibc_test_main.cc
@@ -15,5 +15,5 @@
 #include "sanitizer_common/sanitizer_libc.h"
 
 extern "C" void _start() {
-  internal__exit(0);
+  __sanitizer::internal__exit(0);
 }
Index: lib/sanitizer_common/tests/sanitizer_test_main.cc
===================================================================
--- lib/sanitizer_common/tests/sanitizer_test_main.cc
+++ lib/sanitizer_common/tests/sanitizer_test_main.cc
@@ -19,6 +19,6 @@
   argv0 = argv[0];
   testing::GTEST_FLAG(death_test_style) = "threadsafe";
   testing::InitGoogleTest(&argc, argv);
-  SetCommonFlagsDefaults();
+  __sanitizer::SetCommonFlagsDefaults();
   return RUN_ALL_TESTS();
 }
Index: lib/tsan/rtl/tsan_interface.h
===================================================================
--- lib/tsan/rtl/tsan_interface.h
+++ lib/tsan/rtl/tsan_interface.h
@@ -17,6 +17,7 @@
 #define TSAN_INTERFACE_H
 
 #include <sanitizer_common/sanitizer_internal_defs.h>
+using __sanitizer::uptr;
 
 // This header should NOT include any other headers.
 // All functions in this header are extern "C" and start with __tsan_.
Index: lib/ubsan/ubsan_type_hash_itanium.cc
===================================================================
--- lib/ubsan/ubsan_type_hash_itanium.cc
+++ lib/ubsan/ubsan_type_hash_itanium.cc
@@ -73,6 +73,8 @@
 
 namespace abi = __cxxabiv1;
 
+using namespace __sanitizer;
+
 // We implement a simple two-level cache for type-checking results. For each
 // (vptr,type) pair, a hash is computed. This hash is assumed to be globally
 // unique; if it collides, we will get false negatives, but:
Index: lib/xray/xray_init.cc
===================================================================
--- lib/xray/xray_init.cc
+++ lib/xray/xray_init.cc
@@ -27,6 +27,7 @@
 extern const XRaySledEntry __stop_xray_instr_map[] __attribute__((weak));
 }
 
+using namespace __sanitizer;
 using namespace __xray;
 
 // When set to 'true' this means the XRay runtime has been initialised. We use