diff --git a/libbacktrace/Backtrace.cpp b/libbacktrace/Backtrace.cpp
index 4e4003e..128bb04 100644
--- a/libbacktrace/Backtrace.cpp
+++ b/libbacktrace/Backtrace.cpp
@@ -114,7 +114,9 @@
 }
 
 void Backtrace::FillInMap(uintptr_t pc, backtrace_map_t* map) {
-  map_->FillIn(pc, map);
+  if (map_ != nullptr) {
+    map_->FillIn(pc, map);
+  }
 }
 
 Backtrace* Backtrace::Create(pid_t pid, pid_t tid, BacktraceMap* map) {
diff --git a/libbacktrace/BacktraceCurrent.cpp b/libbacktrace/BacktraceCurrent.cpp
index 14f04de..95cd4d1 100644
--- a/libbacktrace/BacktraceCurrent.cpp
+++ b/libbacktrace/BacktraceCurrent.cpp
@@ -65,6 +65,11 @@
 }
 
 bool BacktraceCurrent::Unwind(size_t num_ignore_frames, ucontext_t* ucontext) {
+  if (GetMap() == nullptr) {
+    // Without a map object, we can't do anything.
+    return false;
+  }
+
   if (ucontext) {
     return UnwindFromContext(num_ignore_frames, ucontext);
   }
diff --git a/libbacktrace/UnwindPtrace.cpp b/libbacktrace/UnwindPtrace.cpp
index a7c3de5..07c2430 100644
--- a/libbacktrace/UnwindPtrace.cpp
+++ b/libbacktrace/UnwindPtrace.cpp
@@ -48,6 +48,11 @@
 }
 
 bool UnwindPtrace::Unwind(size_t num_ignore_frames, ucontext_t* ucontext) {
+  if (GetMap() == nullptr) {
+    // Without a map object, we can't do anything.
+    return false;
+  }
+
   if (ucontext) {
     BACK_LOGW("Unwinding from a specified context not supported yet.");
     return false;