diff --git a/libbacktrace/Android.bp b/libbacktrace/Android.bp
index c58d777..e02aaf2 100644
--- a/libbacktrace/Android.bp
+++ b/libbacktrace/Android.bp
@@ -53,8 +53,6 @@
     "UnwindCurrent.cpp",
     "UnwindMap.cpp",
     "UnwindPtrace.cpp",
-    "UnwindStack.cpp",
-    "UnwindStackMap.cpp",
 ]
 
 cc_library_headers {
@@ -86,7 +84,6 @@
                 "libbase",
                 "liblog",
                 "libunwind",
-                "libunwindstack",
             ],
 
             static_libs: ["libcutils"],
@@ -100,7 +97,6 @@
                 "libbase",
                 "liblog",
                 "libunwind",
-                "libunwindstack",
             ],
 
             static_libs: ["libcutils"],
@@ -112,7 +108,6 @@
                 "libbase",
                 "liblog",
                 "libunwind",
-                "libunwindstack",
             ],
 
             static_libs: ["libasync_safe", "libcutils"],
@@ -135,13 +130,11 @@
         linux: {
             shared_libs: [
                 "libunwind",
-                "libunwindstack",
             ],
         },
         android: {
             shared_libs: [
                 "libunwind",
-                "libunwindstack",
             ],
         },
     }
@@ -168,7 +161,6 @@
     shared_libs = [
         "libbase",
         "libunwind",
-        "libunwindstack",
         "libziparchive",
     ],
 }
@@ -200,7 +192,6 @@
         "libcutils",
         "liblog",
         "libunwind",
-        "libunwindstack",
     ],
 
     group_static_libs: true,
diff --git a/libbacktrace/UnwindStack.cpp b/libbacktrace/UnwindStack.cpp
deleted file mode 100644
index baf0ada..0000000
--- a/libbacktrace/UnwindStack.cpp
+++ /dev/null
@@ -1,220 +0,0 @@
-/*
- * Copyright (C) 2017 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#define _GNU_SOURCE 1
-#include <assert.h>
-#include <stdint.h>
-#include <stdlib.h>
-#include <string.h>
-#include <ucontext.h>
-
-#include <memory>
-#include <string>
-
-#if !defined(__ANDROID__)
-#include <cutils/threads.h>
-#endif
-
-#include <backtrace/Backtrace.h>
-#include <unwindstack/Elf.h>
-#include <unwindstack/MapInfo.h>
-#include <unwindstack/Maps.h>
-#include <unwindstack/Memory.h>
-#include <unwindstack/Regs.h>
-#include <unwindstack/RegsGetLocal.h>
-
-#include "BacktraceLog.h"
-#include "UnwindStack.h"
-#include "UnwindStackMap.h"
-
-static std::string GetFunctionName(pid_t pid, BacktraceMap* back_map, uintptr_t pc,
-                                   uintptr_t* offset) {
-  *offset = 0;
-  unwindstack::Maps* maps = reinterpret_cast<UnwindStackMap*>(back_map)->stack_maps();
-
-  // Get the map for this
-  unwindstack::MapInfo* map_info = maps->Find(pc);
-  if (map_info == nullptr || map_info->flags & PROT_DEVICE_MAP) {
-    return "";
-  }
-
-  unwindstack::Elf* elf = map_info->GetElf(pid, true);
-
-  std::string name;
-  uint64_t func_offset;
-  if (!elf->GetFunctionName(elf->GetRelPc(pc, map_info), &name, &func_offset)) {
-    return "";
-  }
-  *offset = func_offset;
-  return name;
-}
-
-static bool IsUnwindLibrary(const std::string& map_name) {
-  const std::string library(basename(map_name.c_str()));
-  return library == "libunwindstack.so" || library == "libbacktrace.so";
-}
-
-static bool Unwind(pid_t pid, unwindstack::Memory* memory, unwindstack::Regs* regs,
-                   BacktraceMap* back_map, std::vector<backtrace_frame_data_t>* frames,
-                   size_t num_ignore_frames) {
-  unwindstack::Maps* maps = reinterpret_cast<UnwindStackMap*>(back_map)->stack_maps();
-  bool adjust_rel_pc = false;
-  size_t num_frames = 0;
-  frames->clear();
-  while (num_frames < MAX_BACKTRACE_FRAMES) {
-    if (regs->pc() == 0) {
-      break;
-    }
-    unwindstack::MapInfo* map_info = maps->Find(regs->pc());
-    if (map_info == nullptr) {
-      break;
-    }
-
-    unwindstack::Elf* elf = map_info->GetElf(pid, true);
-    uint64_t rel_pc = regs->pc();
-    if (map_info != nullptr) {
-      rel_pc = elf->GetRelPc(regs->pc(), map_info);
-    }
-
-    bool skip_frame = num_frames == 0 && IsUnwindLibrary(map_info->name);
-    if (num_ignore_frames == 0 && !skip_frame) {
-      uint64_t adjusted_rel_pc = rel_pc;
-      if (map_info != nullptr && adjust_rel_pc) {
-        adjusted_rel_pc = regs->GetAdjustedPc(rel_pc, elf);
-      }
-      frames->resize(num_frames + 1);
-      backtrace_frame_data_t* frame = &frames->at(num_frames);
-      frame->num = num_frames;
-      if (map_info != nullptr) {
-        // This will point to the adjusted absolute pc. regs->pc() is
-        // unaltered.
-        frame->pc = map_info->start + adjusted_rel_pc;
-      } else {
-        frame->pc = rel_pc;
-      }
-      frame->sp = regs->sp();
-      frame->rel_pc = adjusted_rel_pc;
-      frame->stack_size = 0;
-
-      frame->map.start = map_info->start;
-      frame->map.end = map_info->end;
-      frame->map.offset = map_info->offset;
-      frame->map.load_bias = elf->GetLoadBias();
-      frame->map.flags = map_info->flags;
-      frame->map.name = map_info->name;
-
-      uint64_t func_offset = 0;
-      if (!elf->GetFunctionName(adjusted_rel_pc, &frame->func_name, &func_offset)) {
-        frame->func_name = "";
-      }
-      frame->func_offset = func_offset;
-      if (num_frames > 0) {
-        // Set the stack size for the previous frame.
-        backtrace_frame_data_t* prev = &frames->at(num_frames - 1);
-        prev->stack_size = frame->sp - prev->sp;
-      }
-      num_frames++;
-    } else if (!skip_frame && num_ignore_frames > 0) {
-      num_ignore_frames--;
-    }
-    adjust_rel_pc = true;
-
-    // Do not unwind through a device map.
-    if (map_info->flags & PROT_DEVICE_MAP) {
-      break;
-    }
-    unwindstack::MapInfo* sp_info = maps->Find(regs->sp());
-    if (sp_info->flags & PROT_DEVICE_MAP) {
-      break;
-    }
-
-    if (!elf->Step(rel_pc + map_info->elf_offset, regs, memory)) {
-      break;
-    }
-  }
-
-  return true;
-}
-
-UnwindStackCurrent::UnwindStackCurrent(pid_t pid, pid_t tid, BacktraceMap* map)
-    : BacktraceCurrent(pid, tid, map), memory_(new unwindstack::MemoryLocal) {}
-
-std::string UnwindStackCurrent::GetFunctionNameRaw(uintptr_t pc, uintptr_t* offset) {
-  return ::GetFunctionName(Pid(), GetMap(), pc, offset);
-}
-
-bool UnwindStackCurrent::UnwindFromContext(size_t num_ignore_frames, ucontext_t* ucontext) {
-  std::unique_ptr<unwindstack::Regs> regs;
-  if (ucontext == nullptr) {
-    regs.reset(unwindstack::Regs::CreateFromLocal());
-    // Fill in the registers from this function. Do it here to avoid
-    // one extra function call appearing in the unwind.
-    unwindstack::RegsGetLocal(regs.get());
-  } else {
-    regs.reset(unwindstack::Regs::CreateFromUcontext(unwindstack::Regs::GetMachineType(), ucontext));
-  }
-
-  error_ = BACKTRACE_UNWIND_NO_ERROR;
-  return ::Unwind(getpid(), memory_.get(), regs.get(), GetMap(), &frames_, num_ignore_frames);
-}
-
-UnwindStackPtrace::UnwindStackPtrace(pid_t pid, pid_t tid, BacktraceMap* map)
-    : BacktracePtrace(pid, tid, map), memory_(new unwindstack::MemoryRemote(pid)) {}
-
-std::string UnwindStackPtrace::GetFunctionNameRaw(uintptr_t pc, uintptr_t* offset) {
-  return ::GetFunctionName(Pid(), GetMap(), pc, offset);
-}
-
-bool UnwindStackPtrace::Unwind(size_t num_ignore_frames, ucontext_t* context) {
-  std::unique_ptr<unwindstack::Regs> regs;
-  if (context == nullptr) {
-    uint32_t machine_type;
-    regs.reset(unwindstack::Regs::RemoteGet(Tid(), &machine_type));
-  } else {
-    regs.reset(unwindstack::Regs::CreateFromUcontext(unwindstack::Regs::GetMachineType(), context));
-  }
-
-  error_ = BACKTRACE_UNWIND_NO_ERROR;
-  return ::Unwind(Pid(), memory_.get(), regs.get(), GetMap(), &frames_, num_ignore_frames);
-}
-
-Backtrace* Backtrace::CreateNew(pid_t pid, pid_t tid, BacktraceMap* map) {
-  if (pid == BACKTRACE_CURRENT_PROCESS) {
-    pid = getpid();
-    if (tid == BACKTRACE_CURRENT_THREAD) {
-      tid = gettid();
-    }
-  } else if (tid == BACKTRACE_CURRENT_THREAD) {
-    tid = pid;
-  }
-
-  if (map == nullptr) {
-// This would cause the wrong type of map object to be created, so disallow.
-#if defined(__ANDROID__)
-    __assert2(__FILE__, __LINE__, __PRETTY_FUNCTION__,
-              "Backtrace::CreateNew() must be called with a real map pointer.");
-#else
-    BACK_LOGE("Backtrace::CreateNew() must be called with a real map pointer.");
-    abort();
-#endif
-  }
-
-  if (pid == getpid()) {
-    return new UnwindStackCurrent(pid, tid, map);
-  } else {
-    return new UnwindStackPtrace(pid, tid, map);
-  }
-}
diff --git a/libbacktrace/UnwindStack.h b/libbacktrace/UnwindStack.h
deleted file mode 100644
index 32d1f51..0000000
--- a/libbacktrace/UnwindStack.h
+++ /dev/null
@@ -1,56 +0,0 @@
-/*
- * Copyright (C) 2017 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#ifndef _LIBBACKTRACE_UNWIND_STACK_H
-#define _LIBBACKTRACE_UNWIND_STACK_H
-
-#include <stdint.h>
-
-#include <string>
-
-#include <backtrace/BacktraceMap.h>
-#include <unwindstack/Memory.h>
-
-#include "BacktraceCurrent.h"
-#include "BacktracePtrace.h"
-
-class UnwindStackCurrent : public BacktraceCurrent {
- public:
-  UnwindStackCurrent(pid_t pid, pid_t tid, BacktraceMap* map);
-  virtual ~UnwindStackCurrent() = default;
-
-  std::string GetFunctionNameRaw(uintptr_t pc, uintptr_t* offset) override;
-
-  bool UnwindFromContext(size_t num_ignore_frames, ucontext_t* ucontext) override;
-
- private:
-  std::unique_ptr<unwindstack::Memory> memory_;
-};
-
-class UnwindStackPtrace : public BacktracePtrace {
- public:
-  UnwindStackPtrace(pid_t pid, pid_t tid, BacktraceMap* map);
-  virtual ~UnwindStackPtrace() = default;
-
-  bool Unwind(size_t num_ignore_frames, ucontext_t* context) override;
-
-  std::string GetFunctionNameRaw(uintptr_t pc, uintptr_t* offset);
-
- private:
-  std::unique_ptr<unwindstack::Memory> memory_;
-};
-
-#endif  // _LIBBACKTRACE_UNWIND_STACK_H
diff --git a/libbacktrace/UnwindStackMap.cpp b/libbacktrace/UnwindStackMap.cpp
deleted file mode 100644
index ba9fd87..0000000
--- a/libbacktrace/UnwindStackMap.cpp
+++ /dev/null
@@ -1,94 +0,0 @@
-/*
- * Copyright (C) 2017 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include <stdint.h>
-#include <stdlib.h>
-#include <sys/types.h>
-
-#include <backtrace/BacktraceMap.h>
-#include <unwindstack/Elf.h>
-#include <unwindstack/MapInfo.h>
-#include <unwindstack/Maps.h>
-
-#include "UnwindStackMap.h"
-
-//-------------------------------------------------------------------------
-UnwindStackMap::UnwindStackMap(pid_t pid) : BacktraceMap(pid) {}
-
-bool UnwindStackMap::Build() {
-  if (pid_ == 0) {
-    pid_ = getpid();
-    stack_maps_.reset(new unwindstack::LocalMaps);
-  } else {
-    stack_maps_.reset(new unwindstack::RemoteMaps(pid_));
-  }
-
-  if (!stack_maps_->Parse()) {
-    return false;
-  }
-
-  // Iterate through the maps and fill in the backtrace_map_t structure.
-  for (auto& map_info : *stack_maps_) {
-    backtrace_map_t map;
-    map.start = map_info.start;
-    map.end = map_info.end;
-    map.offset = map_info.offset;
-    // Set to -1 so that it is demand loaded.
-    map.load_bias = static_cast<uintptr_t>(-1);
-    map.flags = map_info.flags;
-    map.name = map_info.name;
-
-    maps_.push_back(map);
-  }
-
-  return true;
-}
-
-void UnwindStackMap::FillIn(uintptr_t addr, backtrace_map_t* map) {
-  BacktraceMap::FillIn(addr, map);
-  if (map->load_bias != static_cast<uintptr_t>(-1)) {
-    return;
-  }
-
-  // Fill in the load_bias.
-  unwindstack::MapInfo* map_info = stack_maps_->Find(addr);
-  if (map_info == nullptr) {
-    return;
-  }
-  unwindstack::Elf* elf = map_info->GetElf(pid_, true);
-  map->load_bias = elf->GetLoadBias();
-}
-
-//-------------------------------------------------------------------------
-// BacktraceMap create function.
-//-------------------------------------------------------------------------
-BacktraceMap* BacktraceMap::CreateNew(pid_t pid, bool uncached) {
-  BacktraceMap* map;
-
-  if (uncached) {
-    // Force use of the base class to parse the maps when this call is made.
-    map = new BacktraceMap(pid);
-  } else if (pid == getpid()) {
-    map = new UnwindStackMap(0);
-  } else {
-    map = new UnwindStackMap(pid);
-  }
-  if (!map->Build()) {
-    delete map;
-    return nullptr;
-  }
-  return map;
-}
diff --git a/libbacktrace/UnwindStackMap.h b/libbacktrace/UnwindStackMap.h
deleted file mode 100644
index 7885b74..0000000
--- a/libbacktrace/UnwindStackMap.h
+++ /dev/null
@@ -1,41 +0,0 @@
-/*
- * Copyright (C) 2017 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#ifndef _LIBBACKTRACE_UNWINDSTACK_MAP_H
-#define _LIBBACKTRACE_UNWINDSTACK_MAP_H
-
-#include <stdint.h>
-#include <sys/types.h>
-
-#include <backtrace/BacktraceMap.h>
-#include <unwindstack/Maps.h>
-
-class UnwindStackMap : public BacktraceMap {
- public:
-  explicit UnwindStackMap(pid_t pid);
-  ~UnwindStackMap() = default;
-
-  bool Build() override;
-
-  void FillIn(uintptr_t addr, backtrace_map_t* map) override;
-
-  unwindstack::Maps* stack_maps() { return stack_maps_.get(); }
-
- protected:
-  std::unique_ptr<unwindstack::Maps> stack_maps_;
-};
-
-#endif  // _LIBBACKTRACE_UNWINDSTACK_MAP_H
diff --git a/libbacktrace/include/backtrace/Backtrace.h b/libbacktrace/include/backtrace/Backtrace.h
index d67ea50..b919e81 100644
--- a/libbacktrace/include/backtrace/Backtrace.h
+++ b/libbacktrace/include/backtrace/Backtrace.h
@@ -90,8 +90,6 @@
   // If map is NULL, then create the map and manage it internally.
   // If map is not NULL, the map is still owned by the caller.
   static Backtrace* Create(pid_t pid, pid_t tid, BacktraceMap* map = NULL);
-  // Same as above, but uses a different underlying unwinder.
-  static Backtrace* CreateNew(pid_t pid, pid_t tid, BacktraceMap* map = NULL);
 
   // Create an offline Backtrace object that can be used to do an unwind without a process
   // that is still running. If cache_file is set to true, then elf information will be cached
diff --git a/libbacktrace/include/backtrace/BacktraceMap.h b/libbacktrace/include/backtrace/BacktraceMap.h
index 963c34b..02a50f7 100644
--- a/libbacktrace/include/backtrace/BacktraceMap.h
+++ b/libbacktrace/include/backtrace/BacktraceMap.h
@@ -52,8 +52,6 @@
   // Passing a map created with uncached set to true to Backtrace::Create()
   // is unsupported.
   static BacktraceMap* Create(pid_t pid, bool uncached = false);
-  // Same as above, but is compatible with the new unwinder.
-  static BacktraceMap* CreateNew(pid_t pid, bool uncached = false);
 
   static BacktraceMap* Create(pid_t pid, const std::vector<backtrace_map_t>& maps);
 
diff --git a/libunwindstack/include/unwindstack/MapInfo.h b/libunwindstack/include/unwindstack/MapInfo.h
index 1854767..2a97dde 100644
--- a/libunwindstack/include/unwindstack/MapInfo.h
+++ b/libunwindstack/include/unwindstack/MapInfo.h
@@ -41,7 +41,6 @@
   uint64_t elf_offset;
 
   Memory* CreateMemory(pid_t pid);
-  // This function guarantees it will never return nullptr.
   Elf* GetElf(pid_t pid, bool init_gnu_debugdata = false);
 };