diff --git a/debian/changelog b/debian/changelog
index da5ceb69..fc05a895 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -7,6 +7,8 @@ llvm-toolchain-3.9 (1:3.9~+rc3-1) unstable; urgency=medium
   * Use the manpage from clang.rst instead of help2man
   * Fix a crash with clang-tidy (Closes: #833802)
     Fixed in 1:3.9~+rc1-1~exp1
+  * Port to kfreebsd. Many thanks to Pino Toscano
+    (Closes: #835665)
 
  -- Sylvestre Ledru <sylvestre@debian.org>  Fri, 26 Aug 2016 23:34:16 +0200
 
diff --git a/debian/patches/kfreebsd-support.diff b/debian/patches/kfreebsd-support.diff
new file mode 100644
index 00000000..de38cfee
--- /dev/null
+++ b/debian/patches/kfreebsd-support.diff
@@ -0,0 +1,74 @@
+--- a/compiler-rt/cmake/config-ix.cmake
++++ b/compiler-rt/cmake/config-ix.cmake
+@@ -560,7 +560,8 @@ endif()
+ 
+ if (SANITIZER_COMMON_SUPPORTED_ARCH AND NOT LLVM_USE_SANITIZER AND
+     (OS_NAME MATCHES "Android|Darwin|Linux|FreeBSD" OR
+-    (OS_NAME MATCHES "Windows" AND MSVC)))
++    (OS_NAME MATCHES "Windows" AND MSVC))
++    AND NOT (OS_NAME STREQUAL "kFreeBSD"))
+   set(COMPILER_RT_HAS_SANITIZER_COMMON TRUE)
+ else()
+   set(COMPILER_RT_HAS_SANITIZER_COMMON FALSE)
+--- a/tools/llvm-shlib/CMakeLists.txt
++++ b/tools/llvm-shlib/CMakeLists.txt
+@@ -42,7 +42,7 @@ add_llvm_library(LLVM SHARED DISABLE_LLV
+ set_property(TARGET LLVM PROPERTY VERSION "1") # Append .1 to SONAME
+ 
+ list(REMOVE_DUPLICATES LIB_NAMES)
+-if("${CMAKE_SYSTEM_NAME}" STREQUAL "Linux") # FIXME: It should be "GNU ld for elf"
++if("${CMAKE_SYSTEM_NAME}" STREQUAL "Linux" OR "${CMAKE_SYSTEM_NAME}" STREQUAL "GNU" OR "${CMAKE_SYSTEM_NAME}" STREQUAL "kFreeBSD") # FIXME: It should be "GNU ld for elf"
+   # GNU ld doesn't resolve symbols in the version script.
+   set(LIB_NAMES -Wl,--whole-archive ${LIB_NAMES} -Wl,--no-whole-archive)
+ elseif("${CMAKE_SYSTEM_NAME}" STREQUAL "Darwin")
+--- a/lldb/cmake/LLDBDependencies.cmake
++++ b/lldb/cmake/LLDBDependencies.cmake
+@@ -153,7 +153,7 @@ if (NOT CMAKE_SYSTEM_NAME MATCHES "Windo
+   endif()
+ endif()
+ # On FreeBSD/NetBSD backtrace() is provided by libexecinfo, not libc.
+-if (CMAKE_SYSTEM_NAME MATCHES "FreeBSD" OR CMAKE_SYSTEM_NAME MATCHES "NetBSD")
++if ((CMAKE_SYSTEM_NAME MATCHES "FreeBSD" OR CMAKE_SYSTEM_NAME MATCHES "NetBSD") AND NOT CMAKE_SYSTEM_NAME STREQUAL "kFreeBSD")
+   list(APPEND LLDB_SYSTEM_LIBS execinfo)
+ endif()
+ 
+--- a/lldb/scripts/utilsOsType.py
++++ b/lldb/scripts/utilsOsType.py
+@@ -35,6 +35,7 @@ if sys.version_info.major >= 3:
+         Linux = 3
+         NetBSD = 4
+         Windows = 5
++        kFreeBSD = 6
+ else:
+     class EnumOsType(object):
+         values = ["Unknown",
+@@ -42,7 +43,8 @@ else:
+                   "FreeBSD",
+                   "Linux",
+                   "NetBSD",
+-                  "Windows"]
++                  "Windows",
++                  "kFreeBSD"]
+         class __metaclass__(type):
+ #++---------------------------------------------------------------------------
+ # Details:  Fn acts as an enumeration.
+@@ -86,5 +88,7 @@ def determine_os_type():
+         eOSType = EnumOsType.NetBSD
+     elif strOS == "win32":
+         eOSType = EnumOsType.Windows
++    elif strOS.startswith("gnukfreebsd"):
++        eOSType = EnumOsType.kFreeBSD
+ 
+     return eOSType
+--- a/lldb/scripts/Python/modules/CMakeLists.txt
++++ b/lldb/scripts/Python/modules/CMakeLists.txt
+@@ -5,7 +5,7 @@ if (CXX_SUPPORTS_NO_MACRO_REDEFINED)
+   set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-macro-redefined")
+ endif ()
+ 
+-# build the Python readline suppression module only on Linux
+-if (CMAKE_SYSTEM_NAME MATCHES "Linux" AND NOT __ANDROID_NDK__)
++# build the Python readline suppression module only on Linux or GNU systems
++if ((CMAKE_SYSTEM_NAME MATCHES "Linux" OR CMAKE_SYSTEM_NAME STREQUAL "GNU" OR CMAKE_SYSTEM_NAME STREQUAL "kFreeBSD") AND NOT __ANDROID_NDK__)
+    add_subdirectory(readline)
+ endif()
diff --git a/debian/patches/series b/debian/patches/series
index b080d019..ae379d5c 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -33,3 +33,4 @@ disable-test-failing-sparc-i386.diff
 fix-cmake-config-prefix.diff
 lldb-link-atomic-cmake.patch
 disable-llvm-symbolizer-test.diff
+kfreebsd-support.diff