Index: libunwind/cmake/config-ix.cmake
===================================================================
--- libunwind/cmake/config-ix.cmake
+++ libunwind/cmake/config-ix.cmake
@@ -11,7 +11,11 @@
 # --unwindlib=none is supported, and use that if possible.
 llvm_check_compiler_linker_flag(C "--unwindlib=none" CXX_SUPPORTS_UNWINDLIB_EQ_NONE_FLAG)

-check_library_exists(c fopen "" LIBUNWIND_HAS_C_LIB)
+if (HAIKU)
+  check_library_exists(root fopen "" LIBUNWIND_HAS_ROOT_LIB)
+else()
+  check_library_exists(c fopen "" LIBUNWIND_HAS_C_LIB)
+endif()

 if (NOT LIBUNWIND_USE_COMPILER_RT)
   if (ANDROID)
@@ -45,6 +49,9 @@
   if (LIBUNWIND_HAS_C_LIB)
     list(APPEND CMAKE_REQUIRED_LIBRARIES c)
   endif ()
+  if (LIBUNWIND_HAS_ROOT_LIB)
+    list(APPEND CMAKE_REQUIRED_LIBRARIES root)
+  endif ()
   if (LIBUNWIND_USE_COMPILER_RT)
     include(HandleCompilerRT)
     find_compiler_rt_library(builtins LIBUNWIND_BUILTINS_LIBRARY
@@ -111,3 +118,7 @@
   check_library_exists(dl dladdr "" LIBUNWIND_HAS_DL_LIB)
   check_library_exists(pthread pthread_once "" LIBUNWIND_HAS_PTHREAD_LIB)
 endif()
+
+if(HAIKU)
+  check_library_exists(bsd dl_iterate_phdr "" LIBUNWIND_HAS_BSD_LIB)
+endif()
Index: libunwind/include/__libunwind_config.h
===================================================================
--- libunwind/include/__libunwind_config.h
+++ libunwind/include/__libunwind_config.h
@@ -36,6 +36,9 @@
 # if defined(__linux__)
 #  define _LIBUNWIND_TARGET_LINUX 1
 # endif
+# if defined(__HAIKU__)
+#  define _LIBUNWIND_TARGET_HAIKU 1
+# endif
 # if defined(__i386__)
 #  define _LIBUNWIND_TARGET_I386
 #  define _LIBUNWIND_CONTEXT_SIZE 8
Index: libunwind/src/CMakeLists.txt
===================================================================
--- libunwind/src/CMakeLists.txt
+++ libunwind/src/CMakeLists.txt
@@ -102,6 +102,16 @@
   endif ()
 endif ()

+if (HAIKU)
+  add_library_flags_if(LIBUNWIND_HAS_ROOT_LIB root)
+
+  add_library_flags_if(LIBUNWIND_HAS_BSD_LIB bsd)
+  add_compile_flags_if(LIBUNWIND_HAS_BSD_LIB -D_LIBUNWIND_USE_HAIKU_BSD_LIB=1)
+
+  add_compile_flags("-D_DEFAULT_SOURCE")
+  add_compile_flags("-DPT_GNU_EH_FRAME=PT_EH_FRAME")
+endif ()
+
 string(REPLACE ";" " " LIBUNWIND_COMPILE_FLAGS "${LIBUNWIND_COMPILE_FLAGS}")
 string(REPLACE ";" " " LIBUNWIND_CXX_FLAGS "${LIBUNWIND_CXX_FLAGS}")
 string(REPLACE ";" " " LIBUNWIND_C_FLAGS "${LIBUNWIND_C_FLAGS}")
Index: libunwind/src/config.h
===================================================================
--- libunwind/src/config.h
+++ libunwind/src/config.h
@@ -46,6 +46,12 @@
 #elif defined(_AIX)
 // The traceback table at the end of each function is used for unwinding.
 #define _LIBUNWIND_SUPPORT_TBTAB_UNWIND 1
+#elif defined(__HAIKU__)
+  #if defined(_LIBUNWIND_USE_HAIKU_BSD_LIB)
+    #define _LIBUNWIND_USE_DL_ITERATE_PHDR 1
+  #endif
+  #define _LIBUNWIND_SUPPORT_DWARF_UNWIND 1
+  #define _LIBUNWIND_SUPPORT_DWARF_INDEX 1
 #else
   // Assume an ELF system with a dl_iterate_phdr function.
   #define _LIBUNWIND_USE_DL_ITERATE_PHDR 1
Index: libunwind/test/configs/llvm-libunwind-shared.cfg.in
===================================================================
--- libunwind/test/configs/llvm-libunwind-shared.cfg.in
+++ libunwind/test/configs/llvm-libunwind-shared.cfg.in
@@ -24,7 +24,7 @@
     '-nostdinc++ -I %{{include}} {}'.format(' '.join(compile_flags))
 ))
 config.substitutions.append(('%{link_flags}',
-    '-L %{{lib}} -Wl,-rpath,%{{lib}} -lunwind -ldl {}'.format(' '.join(link_flags))
+    '-L %{{lib}} -Wl,-rpath,%{{lib}} -lunwind @CMAKE_DL_LIBS@ {}'.format(' '.join(link_flags))
 ))
 config.substitutions.append(('%{exec}',
     '%{executor} --execdir %T -- '