--- a/lldb/source/Host/common/Host.cpp
+++ b/lldb/source/Host/common/Host.cpp
@@ -27,7 +27,7 @@
 #include <mach-o/dyld.h>
 #include <mach/mach_port.h>
 
-#elif defined (__linux__) || defined(__FreeBSD_kernel__)
+#elif defined (__linux__) || defined(__GLIBC__)
 /*  Linux or the FreeBSD kernel with glibc (Debian KFreeBSD for example) */
 
 #include <sys/wait.h>
@@ -524,7 +524,7 @@
 {
 }
 
-#if !defined (__APPLE__) && !defined (__FreeBSD__) && !defined (__linux__) // see macosx/Host.mm
+#if !defined (__APPLE__) && !defined (__FreeBSD__) && !defined (__FreeBSD_kernel__) && !defined (__linux__) // see macosx/Host.mm
 
 void
 Host::ThreadCreated (const char *thread_name)
@@ -544,7 +544,7 @@
     return 0;
 }
 
-#endif // #if !defined (__APPLE__) && !defined (__FreeBSD__) && !defined (__linux__)
+#endif // #if !defined (__APPLE__) && !defined (__FreeBSD__) && !defined (__FreeBSD_kernel__) && !defined (__linux__)
 
 struct HostThreadCreateInfo
 {
@@ -684,7 +684,7 @@
             return true;
     }
     return false;
-#elif defined (__linux__)
+#elif defined (__linux__) || defined (__GLIBC__)
     void *fn = dlsym (RTLD_DEFAULT, "pthread_setname_np");
     if (fn)
     {
@@ -742,7 +742,7 @@
             exe_path[len] = 0;
             g_program_filespec.SetFile(exe_path, false);
         }
-#elif defined (__FreeBSD__)
+#elif defined (__FreeBSD__) || defined (__FreeBSD_kernel__)
         int exe_path_mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, getpid() };
         size_t exe_path_size;
         if (sysctl(exe_path_mib, 4, NULL, &exe_path_size, NULL, 0) == 0)
@@ -1180,7 +1180,7 @@
     return NULL;
 }
 
-#if !defined (__APPLE__) && !defined (__FreeBSD__) // see macosx/Host.mm
+#if !defined (__APPLE__) && !defined (__FreeBSD__) && !defined (__FreeBSD_kernel__) // see macosx/Host.mm
 bool
 Host::GetOSBuildString (std::string &s)
 {
@@ -1229,7 +1229,7 @@
 }
 #endif // #if !defined (__APPLE__) && !defined(__linux__)
 
-#if !defined (__APPLE__) && !defined (__FreeBSD__) && !defined(__linux__)
+#if !defined (__APPLE__) && !defined (__FreeBSD__) && !defined (__FreeBSD_kernel__) && !defined(__linux__)
 bool
 Host::GetProcessInfo (lldb::pid_t pid, ProcessInstanceInfo &process_info)
 {
@@ -1443,7 +1443,7 @@
     static uint32_t g_num_cores = UINT32_MAX;
     if (g_num_cores == UINT32_MAX)
     {
-#if defined(__APPLE__) or defined (__linux__) or defined (__FreeBSD__)
+#if defined(__APPLE__) or defined (__linux__) or defined (__FreeBSD__) or defined (__FreeBSD_kernel__)
 
         g_num_cores = ::sysconf(_SC_NPROCESSORS_ONLN);
         
--- a/Makefile.rules
+++ b/Makefile.rules
@@ -275,10 +275,12 @@
   BuildMode := Release
   # Don't use -fomit-frame-pointer on Darwin or FreeBSD.
   ifneq ($(HOST_OS),FreeBSD)
+  ifneq ($(HOST_OS),GNU/kFreeBSD)
   ifneq ($(HOST_OS),Darwin)
     OmitFramePointer := -fomit-frame-pointer
   endif
   endif
+  endif
 
   CXX.Flags += $(OPTIMIZE_OPTION) $(OmitFramePointer)
   C.Flags   += $(OPTIMIZE_OPTION) $(OmitFramePointer)
@@ -1454,7 +1456,7 @@
 endif
 endif
 
-ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux NetBSD FreeBSD GNU))
+ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux NetBSD FreeBSD GNU/kFreeBSD GNU))
 ifneq ($(ARCH), Mips)
   LD.Flags += -Wl,--version-script=$(LLVM_SRC_ROOT)/autoconf/ExportMap.map
 endif
--- a/autoconf/configure.ac
+++ b/autoconf/configure.ac
@@ -222,11 +222,16 @@
     llvm_cv_no_link_all_option="-Wl,-noall_load"
     llvm_cv_os_type="Minix"
     llvm_cv_platform_type="Unix" ;;
-  *-*-freebsd* | *-*-kfreebsd-gnu)
+  *-*-freebsd*)
     llvm_cv_link_all_option="-Wl,--whole-archive"
     llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
     llvm_cv_os_type="FreeBSD"
     llvm_cv_platform_type="Unix" ;;
+  *-*-kfreebsd-gnu)
+    llvm_cv_link_all_option="-Wl,--whole-archive"
+    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
+    llvm_cv_os_type="GNU/kFreeBSD"
+    llvm_cv_platform_type="Unix" ;;
   *-*-openbsd*)
     llvm_cv_link_all_option="-Wl,--whole-archive"
     llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
@@ -317,8 +322,10 @@
     llvm_cv_target_os_type="Darwin" ;;
   *-*-minix*)
     llvm_cv_target_os_type="Minix" ;;
-  *-*-freebsd* | *-*-kfreebsd-gnu)
+  *-*-freebsd*)
     llvm_cv_target_os_type="FreeBSD" ;;
+  *-*-kfreebsd-gnu)
+    llvm_cv_target_os_type="GNU/kFreeBSD" ;;
   *-*-openbsd*)
     llvm_cv_target_os_type="OpenBSD" ;;
   *-*-netbsd*)
--- a/clang/tools/libclang/Makefile
+++ b/clang/tools/libclang/Makefile
@@ -30,7 +30,7 @@
 include $(CLANG_LEVEL)/Makefile
 
 # Add soname to the library.
-ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux FreeBSD GNU))
+ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux FreeBSD GNU GNU/kFreeBSD))
         LDFLAGS += -Wl,-soname,lib$(LIBRARYNAME)$(SHLIBEXT).$(SONAME_MAJOR)
 endif
 
--- a/configure
+++ b/configure
@@ -3824,11 +3824,16 @@
     llvm_cv_no_link_all_option="-Wl,-noall_load"
     llvm_cv_os_type="Minix"
     llvm_cv_platform_type="Unix" ;;
-  *-*-freebsd* | *-*-kfreebsd-gnu)
+  *-*-freebsd*)
     llvm_cv_link_all_option="-Wl,--whole-archive"
     llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
     llvm_cv_os_type="FreeBSD"
     llvm_cv_platform_type="Unix" ;;
+  *-*-kfreebsd-gnu)
+    llvm_cv_link_all_option="-Wl,--whole-archive"
+    llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
+    llvm_cv_os_type="GNU/kFreeBSD"
+    llvm_cv_platform_type="Unix" ;;
   *-*-openbsd*)
     llvm_cv_link_all_option="-Wl,--whole-archive"
     llvm_cv_no_link_all_option="-Wl,--no-whole-archive"
@@ -3925,8 +3930,10 @@
     llvm_cv_target_os_type="Darwin" ;;
   *-*-minix*)
     llvm_cv_target_os_type="Minix" ;;
-  *-*-freebsd* | *-*-kfreebsd-gnu)
+  *-*-freebsd*)
     llvm_cv_target_os_type="FreeBSD" ;;
+  *-*-kfreebsd-gnu)
+    llvm_cv_target_os_type="GNU/kFreeBSD" ;;
   *-*-openbsd*)
     llvm_cv_target_os_type="OpenBSD" ;;
   *-*-netbsd*)
--- a/lldb/lib/Makefile
+++ b/lldb/lib/Makefile
@@ -99,7 +99,7 @@
               lldbPluginDynamicLoaderMacOSX.a
 endif
 
-ifeq ($(HOST_OS),FreeBSD)
+ifneq (,$(filter $(HOST_OS), FreeBSD GNU/kFreeBSD))
   USEDLIBS += lldbHostFreeBSD.a \
               lldbPluginProcessPOSIX.a \
               lldbPluginProcessFreeBSD.a
@@ -132,7 +132,7 @@
     endif
 endif
 
-ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux GNU))
+ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux GNU GNU/kFreeBSD))
     # Include everything from the .a's into the shared library.
     ProjLibsOptions := -Wl,--whole-archive $(ProjLibsOptions) \
                        -Wl,--no-whole-archive
--- a/lldb/source/Host/Makefile
+++ b/lldb/source/Host/Makefile
@@ -21,7 +21,7 @@
 DIRS += linux
 endif
 
-ifeq ($(HOST_OS),FreeBSD)
+ifneq (,$(filter $(HOST_OS), FreeBSD GNU/kFreeBSD))
 DIRS += freebsd
 endif
 
--- a/lldb/source/Plugins/Platform/Makefile
+++ b/lldb/source/Plugins/Platform/Makefile
@@ -24,5 +24,9 @@
 # ifeq ($(HOST_OS),FreeBSD)
 #   DIRS += FreeBSD
 # endif
+# 
+# ifeq ($(HOST_OS),GNU/kFreeBSD)
+#   DIRS += FreeBSD
+# endif
 
 include $(LLDB_LEVEL)/Makefile
--- a/lldb/source/Plugins/Process/POSIX/Makefile
+++ b/lldb/source/Plugins/Process/POSIX/Makefile
@@ -24,7 +24,7 @@
 CPPFLAGS += -Wno-extended-offsetof
 endif
 
-ifeq ($(HOST_OS),FreeBSD)
+ifneq (,$(filter $(HOST_OS), FreeBSD GNU/kFreeBSD))
 # Extend the include path so we may locate ProcessMonitor
 CPPFLAGS += -I$(PROJ_SRC_DIR)/$(LLDB_LEVEL)/source/Plugins/Process/FreeBSD
 endif
--- a/projects/sample/Makefile.llvm.rules
+++ b/projects/sample/Makefile.llvm.rules
@@ -208,10 +208,12 @@
   BuildMode := Release
   # Don't use -fomit-frame-pointer on Darwin or FreeBSD.
   ifneq ($(HOST_OS),FreeBSD)
+  ifneq ($(HOST_OS),GNU/kFreeBSD)
   ifneq ($(HOST_OS),Darwin)
     OmitFramePointer := -fomit-frame-pointer
   endif
   endif
+  endif
 
   # Darwin requires -fstrict-aliasing to be explicitly enabled.
   # Avoid -fstrict-aliasing on Darwin for now, there are unresolved issues
@@ -1372,7 +1374,7 @@
 endif
 endif
 
-ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux NetBSD FreeBSD))
+ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux NetBSD FreeBSD GNU/kFreeBSD))
 ifneq ($(ARCH), Mips)
   LD.Flags += -Wl,--version-script=$(PROJ_SRC_ROOT)/autoconf/ExportMap.map
 endif
--- a/tools/llvm-shlib/Makefile
+++ b/tools/llvm-shlib/Makefile
@@ -69,18 +69,18 @@
     endif
 endif
 
-ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux FreeBSD OpenBSD GNU Bitrig))
+ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux FreeBSD GNU/kFreeBSD OpenBSD GNU Bitrig))
     # Include everything from the .a's into the shared library.
     LLVMLibsOptions := -Wl,--whole-archive $(LLVMLibsOptions) \
                        -Wl,--no-whole-archive
 endif
 
-ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux FreeBSD GNU))
+ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux FreeBSD GNU/kFreeBSD GNU))
     # Add soname to the library.
     LLVMLibsOptions += -Wl,--soname,lib$(LIBRARYNAME)$(SHLIBEXT).1 -Wl,-Bsymbolic-functions
 endif
 
-ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux GNU))
+ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux GNU GNU/kFreeBSD))
     # Don't allow unresolved symbols.
     LLVMLibsOptions += -Wl,--no-undefined
 endif
--- a/lldb/source/Plugins/Makefile
+++ b/lldb/source/Plugins/Makefile
@@ -36,7 +36,7 @@
 DIRS += Process/Linux Process/POSIX
 endif
 
-ifeq ($(HOST_OS),FreeBSD)
+ifneq (,$(filter $(HOST_OS), FreeBSD GNU/kFreeBSD))
 DIRS += Process/FreeBSD Process/POSIX
 endif
 
--- a/lldb/tools/driver/Makefile
+++ b/lldb/tools/driver/Makefile
@@ -21,7 +21,7 @@
 	LLVMLibsOptions += -Wl,-sectcreate -Wl,__TEXT -Wl,__info_plist -Wl,"$(PROJ_SRC_DIR)/lldb-Info.plist"
 endif
 
-ifeq ($(HOST_OS),Linux)
+ifneq (,$(filter $(HOST_OS), Linux GNU/kFreeBSD))
 	LLVMLibsOptions += -Wl,-rpath,$(LibDir)
 endif
 
--- a/lldb/tools/lldb-platform/Makefile
+++ b/lldb/tools/lldb-platform/Makefile
@@ -18,6 +18,6 @@
 	LLVMLibsOptions += -Wl,-rpath,@loader_path/../lib/
 endif
 
-ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux FreeBSD))
+ifeq ($(HOST_OS), $(filter $(HOST_OS), Linux FreeBSD GNU/kFreeBSD))
 	LLVMLibsOptions += -Wl,-rpath,$(LibDir)
 endif