Index: cmake/config-ix.cmake
===================================================================
--- cmake/config-ix.cmake
+++ cmake/config-ix.cmake
@@ -13,7 +13,7 @@
 
 include(HandleLLVMStdlib)
 
-if( UNIX AND NOT BEOS )
+if( UNIX AND NOT (BEOS OR HAIKU) )
   # Used by check_symbol_exists:
   set(CMAKE_REQUIRED_LIBRARIES m)
 endif()
Index: cmake/config.guess
===================================================================
--- cmake/config.guess
+++ cmake/config.guess
@@ -1203,6 +1203,9 @@
     BePC:Haiku:*:*)	# Haiku running on Intel PC compatible.
 	echo i586-pc-haiku
 	exit ;;
+    x86_64:Haiku:*:*) # Haiku running on x86_64.
+	echo x86_64-unknown-haiku
+	exit ;;
     SX-4:SUPER-UX:*:*)
 	echo sx4-nec-superux${UNAME_RELEASE}
 	exit ;;
Index: include/llvm/Support/Host.h
===================================================================
--- include/llvm/Support/Host.h
+++ include/llvm/Support/Host.h
@@ -16,7 +16,7 @@
 
 #include "llvm/ADT/StringMap.h"
 
-#if defined(__linux__) || defined(__GNU__)
+#if defined(__linux__) || defined(__GNU__) || defined(__HAIKU__)
 #include <endian.h>
 #else
 #if !defined(BYTE_ORDER) && !defined(LLVM_ON_WIN32)
Index: lib/Support/CMakeLists.txt
===================================================================
--- lib/Support/CMakeLists.txt
+++ lib/Support/CMakeLists.txt
@@ -24,7 +24,9 @@
     if ( LLVM_ENABLE_ZLIB AND HAVE_LIBZ )
       set(system_libs ${system_libs} z)
     endif()
-    set(system_libs ${system_libs} m)
+    if( UNIX AND NOT (BEOS OR HAIKU) )
+      set(system_libs ${system_libs} m)
+    endif()
   endif( MINGW )
 endif( NOT MSVC )