diff --git a/compiler-rt/lib/asan/asan_allocator.h b/compiler-rt/lib/asan/asan_allocator.h
--- a/compiler-rt/lib/asan/asan_allocator.h
+++ b/compiler-rt/lib/asan/asan_allocator.h
@@ -17,6 +17,7 @@
 #include "asan_flags.h"
 #include "asan_interceptors.h"
 #include "asan_internal.h"
+#include "lsan/lsan_allocator.h"
 #include "sanitizer_common/sanitizer_allocator.h"
 #include "sanitizer_common/sanitizer_list.h"
 #include "sanitizer_common/sanitizer_platform.h"
@@ -118,12 +119,9 @@
 };
 
 #if SANITIZER_CAN_USE_ALLOCATOR64
-# if SANITIZER_FUCHSIA
-const uptr kAllocatorSpace = ~(uptr)0;
-const uptr kAllocatorSize  =  0x40000000000ULL;  // 4T.
-typedef DefaultSizeClassMap SizeClassMap;
-# elif defined(__powerpc64__)
+# if defined(__powerpc64__)
 const uptr kAllocatorSpace = ~(uptr)0;
+// NOTE: This differs slightly from the LSan allocator size which is 4T.
 const uptr kAllocatorSize  =  0x20000000000ULL;  // 2T.
 typedef DefaultSizeClassMap SizeClassMap;
 # elif defined(__aarch64__) && SANITIZER_ANDROID
@@ -150,8 +148,9 @@
 const uptr kAllocatorSize  =  0x8000000000ULL;  // 500G
 typedef DefaultSizeClassMap SizeClassMap;
 # else
-const uptr kAllocatorSpace = 0x600000000000ULL;
-const uptr kAllocatorSize  =  0x40000000000ULL;  // 4T.
+// Use LSan's allocator configs.
+const uptr kAllocatorSpace = __lsan::kAllocatorSpace;
+const uptr kAllocatorSize  = __lsan::kAllocatorSize;
 typedef DefaultSizeClassMap SizeClassMap;
 # endif
 template <typename AddressSpaceViewTy>