diff --git a/libc/bionic/android_unsafe_frame_pointer_chase.cpp b/libc/bionic/android_unsafe_frame_pointer_chase.cpp
index 0fb086e..e25867b 100644
--- a/libc/bionic/android_unsafe_frame_pointer_chase.cpp
+++ b/libc/bionic/android_unsafe_frame_pointer_chase.cpp
@@ -57,6 +57,12 @@
 
   auto begin = reinterpret_cast<uintptr_t>(__builtin_frame_address(0));
   uintptr_t end = __get_thread()->stack_top;
+
+  stack_t ss;
+  if (sigaltstack(nullptr, &ss) == 0 && (ss.ss_flags & SS_ONSTACK)) {
+    end = reinterpret_cast<uintptr_t>(ss.ss_sp) + ss.ss_size;
+  }
+
   size_t num_frames = 0;
   while (1) {
     auto* frame = reinterpret_cast<frame_record*>(begin);