Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp
@@ -83,9 +83,14 @@
 extern "C" {
 // <sys/umtx.h> must be included after <errno.h> and <sys/types.h> on
 // FreeBSD 9.2 and 10.0.
+#if SANITIZER_KFREEBSD
+#include <bsd/sys/cdefs.h>
+#endif
 #include <sys/umtx.h>
 }
+#if !SANITIZER_KFREEBSD
 #include <sys/thr.h>
+#endif
 #endif  // SANITIZER_FREEBSD
 
 #if SANITIZER_NETBSD
@@ -461,10 +466,12 @@ bool FileExists(const char *filename) {
 
 #if !SANITIZER_NETBSD
 tid_t GetTid() {
-#if SANITIZER_FREEBSD
+#if SANITIZER_FREEBSD && !SANITIZER_KFREEBSD
   long Tid;
   thr_self(&Tid);
   return Tid;
+#elif SANITIZER_KFREEBSD
+  return (uptr)pthread_self();
 #elif SANITIZER_OPENBSD
   return internal_syscall(SYSCALL(getthrid));
 #elif SANITIZER_SOLARIS
@@ -1148,10 +1155,10 @@ bool LibraryNameIs(const char *full_name
 // Call cb for each region mapped by map.
 void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr)) {
   CHECK_NE(map, nullptr);
-#if !SANITIZER_FREEBSD && !SANITIZER_OPENBSD
+#if !SANITIZER_FREEBSD && !SANITIZER_OPENBSD || SANITIZER_KFREEBSD
   typedef ElfW(Phdr) Elf_Phdr;
   typedef ElfW(Ehdr) Elf_Ehdr;
-#endif // !SANITIZER_FREEBSD && !SANITIZER_OPENBSD
+#endif // !SANITIZER_FREEBSD && !SANITIZER_OPENBSD || SANITIZER_KFREEBSD
   char *base = (char *)map->l_addr;
   Elf_Ehdr *ehdr = (Elf_Ehdr *)base;
   char *phdrs = base + ehdr->e_phoff;
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
@@ -36,10 +36,12 @@
 #include <syslog.h>
 
 #if SANITIZER_FREEBSD
-#include <pthread_np.h>
+# if !SANITIZER_KFREEBSD
+# include <pthread_np.h>
+# define pthread_getattr_np pthread_attr_get_np
+# endif
 #include <osreldate.h>
 #include <sys/sysctl.h>
-#define pthread_getattr_np pthread_attr_get_np
 #endif
 
 #if SANITIZER_OPENBSD
@@ -525,9 +527,9 @@ void GetThreadStackAndTls(bool main, upt
 #endif
 }
 
-#if !SANITIZER_FREEBSD && !SANITIZER_OPENBSD
+#if !SANITIZER_FREEBSD && !SANITIZER_OPENBSD || SANITIZER_KFREEBSD
 typedef ElfW(Phdr) Elf_Phdr;
-#elif SANITIZER_WORDSIZE == 32 && __FreeBSD_version <= 902001 // v9.2
+#elif SANITIZER_WORDSIZE == 32 && !SANITIZER_KFREEBSD && __FreeBSD_version <= 902001 // v9.2
 #define Elf_Phdr XElf32_Phdr
 #define dl_phdr_info xdl_phdr_info
 #define dl_iterate_phdr(c, b) xdl_iterate_phdr((c), (b))
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_platform.h
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/sanitizer_common/sanitizer_platform.h
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_platform.h
@@ -15,7 +15,7 @@
 #if !defined(__linux__) && !defined(__FreeBSD__) && !defined(__NetBSD__) && \
   !defined(__OpenBSD__) && !defined(__APPLE__) && !defined(_WIN32) && \
   !defined(__Fuchsia__) && !defined(__rtems__) && \
-  !(defined(__sun__) && defined(__svr4__))
+  !(defined(__sun__) && defined(__svr4__)) && !defined(__FreeBSD_kernel__)
 # error "This operating system is not supported"
 #endif
 
@@ -25,12 +25,18 @@
 # define SANITIZER_LINUX   0
 #endif
 
-#if defined(__FreeBSD__)
+#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 # define SANITIZER_FREEBSD 1
 #else
 # define SANITIZER_FREEBSD 0
 #endif
 
+#if defined(__FreeBSD_kernel__)
+# define SANITIZER_KFREEBSD 1
+#else
+# define SANITIZER_KFREEBSD 0
+#endif
+
 #if defined(__NetBSD__)
 # define SANITIZER_NETBSD 1
 #else
@@ -112,7 +118,8 @@
 
 #define SANITIZER_POSIX \
   (SANITIZER_FREEBSD || SANITIZER_LINUX || SANITIZER_MAC || \
-    SANITIZER_NETBSD || SANITIZER_OPENBSD || SANITIZER_SOLARIS)
+    SANITIZER_NETBSD || SANITIZER_OPENBSD || SANITIZER_SOLARIS || \
+    SANITIZER_KFREEBSD)
 
 #if __LP64__ || defined(_WIN64)
 #  define SANITIZER_WORDSIZE 64
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/asan/asan_linux.cpp
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/asan/asan_linux.cpp
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/asan/asan_linux.cpp
@@ -37,7 +37,7 @@
 #include <unistd.h>
 #include <unwind.h>
 
-#if SANITIZER_FREEBSD
+#if SANITIZER_FREEBSD && !SANITIZER_KFREEBSD
 #include <sys/link_elf.h>
 #endif
 
@@ -47,7 +47,11 @@
 
 #if SANITIZER_ANDROID || SANITIZER_FREEBSD || SANITIZER_SOLARIS
 #include <ucontext.h>
+#if SANITIZER_KFREEBSD
+#include <link.h>
+#else
 extern "C" void* _DYNAMIC;
+#endif
 #elif SANITIZER_NETBSD
 #include <link_elf.h>
 #include <ucontext.h>
@@ -60,7 +64,7 @@ extern Elf_Dyn _DYNAMIC;
 // x86-64 FreeBSD 9.2 and older define 'ucontext_t' incorrectly in
 // 32-bit mode.
 #if SANITIZER_FREEBSD && (SANITIZER_WORDSIZE == 32) && \
-  __FreeBSD_version <= 902001  // v9.2
+  !SANITIZER_KFREEBSD && __FreeBSD_version <= 902001  // v9.2
 #define ucontext_t xucontext_t
 #endif
 
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/ubsan/ubsan_platform.h
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/ubsan/ubsan_platform.h
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/ubsan/ubsan_platform.h
@@ -14,7 +14,7 @@
 
 // Other platforms should be easy to add, and probably work as-is.
 #if defined(__linux__) || defined(__FreeBSD__) || defined(__APPLE__) ||        \
-    defined(__NetBSD__) || defined(__OpenBSD__) || \
+    defined(__NetBSD__) || defined(__OpenBSD__) || defined(__FreeBSD_kernel__) || \
     (defined(__sun__) && defined(__svr4__)) || \
     defined(_WIN32) || defined(__Fuchsia__) || defined(__rtems__)
 # define CAN_SANITIZE_UB 1
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/tsan/rtl/tsan_rtl_amd64.S
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/tsan/rtl/tsan_rtl_amd64.S
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/tsan/rtl/tsan_rtl_amd64.S
@@ -192,7 +192,7 @@ ASM_SYMBOL_INTERCEPTOR(setjmp):
   // obtain SP, store in %rdi, first argument to `void __tsan_setjmp(uptr sp)`
 #if defined(__FreeBSD__) || defined(__NetBSD__)
   lea 8(%rsp), %rdi
-#elif defined(__linux__) || defined(__APPLE__)
+#elif defined(__linux__) || defined(__FreeBSD_kernel__) || defined(__APPLE__)
   lea 16(%rsp), %rdi
 #else
 # error "Unknown platform"
@@ -233,7 +233,7 @@ ASM_SYMBOL_INTERCEPTOR(_setjmp):
   // obtain SP, store in %rdi, first argument to `void __tsan_setjmp(uptr sp)`
 #if defined(__FreeBSD__) || defined(__NetBSD__)
   lea 8(%rsp), %rdi
-#elif defined(__linux__) || defined(__APPLE__)
+#elif defined(__linux__) || defined(__FreeBSD_kernel__) || defined(__APPLE__)
   lea 16(%rsp), %rdi
 #else
 # error "Unknown platform"
@@ -281,7 +281,7 @@ ASM_SYMBOL_INTERCEPTOR(sigsetjmp):
   // obtain SP, store in %rdi, first argument to `void __tsan_setjmp(uptr sp)`
 #if defined(__FreeBSD__) || defined(__NetBSD__)
   lea 24(%rsp), %rdi
-#elif defined(__linux__) || defined(__APPLE__)
+#elif defined(__linux__) || defined(__FreeBSD_kernel__) || defined(__APPLE__)
   lea 32(%rsp), %rdi
 #else
 # error "Unknown platform"
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/fuzzer/FuzzerDefs.h
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/fuzzer/FuzzerDefs.h
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/fuzzer/FuzzerDefs.h
@@ -28,6 +28,7 @@
 #define LIBFUZZER_LINUX 1
 #define LIBFUZZER_NETBSD 0
 #define LIBFUZZER_FREEBSD 0
+#define LIBFUZZER_KFREEBSD 1
 #define LIBFUZZER_OPENBSD 0
 #define LIBFUZZER_WINDOWS 0
 #elif __APPLE__
@@ -54,6 +55,15 @@
 #define LIBFUZZER_FREEBSD 1
 #define LIBFUZZER_OPENBSD 0
 #define LIBFUZZER_WINDOWS 0
+#elif __FreeBSD_kernel__
+#define LIBFUZZER_APPLE 0
+#define LIBFUZZER_FUCHSIA 0
+#define LIBFUZZER_LINUX 0
+#define LIBFUZZER_NETBSD 0
+#define LIBFUZZER_FREEBSD 0
+#define LIBFUZZER_KFREEBSD 1
+#define LIBFUZZER_OPENBSD 0
+#define LIBFUZZER_WINDOWS 0
 #elif __OpenBSD__
 #define LIBFUZZER_APPLE 0
 #define LIBFUZZER_FUCHSIA 0
@@ -95,7 +105,7 @@
 
 #define LIBFUZZER_POSIX                                                        \
   (LIBFUZZER_APPLE || LIBFUZZER_LINUX || LIBFUZZER_NETBSD ||                   \
-   LIBFUZZER_FREEBSD || LIBFUZZER_OPENBSD)
+   LIBFUZZER_FREEBSD || LIBFUZZER_OPENBSD || LIBFUZZER_KFREEBSD)
 
 #ifdef __x86_64
 #  if __has_attribute(target)
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/fuzzer/FuzzerUtilPosix.cpp
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/fuzzer/FuzzerUtilPosix.cpp
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/fuzzer/FuzzerUtilPosix.cpp
@@ -133,7 +133,7 @@ size_t GetPeakRSSMb() {
   if (getrusage(RUSAGE_SELF, &usage))
     return 0;
   if (LIBFUZZER_LINUX || LIBFUZZER_FREEBSD || LIBFUZZER_NETBSD ||
-      LIBFUZZER_OPENBSD) {
+      LIBFUZZER_OPENBSD || LIBFUZZER_KFREEBSD) {
     // ru_maxrss is in KiB
     return usage.ru_maxrss >> 10;
   } else if (LIBFUZZER_APPLE) {
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/fuzzer/FuzzerExtraCounters.cpp
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/fuzzer/FuzzerExtraCounters.cpp
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/fuzzer/FuzzerExtraCounters.cpp
@@ -11,7 +11,7 @@
 #include "FuzzerDefs.h"
 
 #if LIBFUZZER_LINUX || LIBFUZZER_NETBSD || LIBFUZZER_FREEBSD ||                \
-    LIBFUZZER_OPENBSD
+    LIBFUZZER_OPENBSD || LIBFUZZER_KFREEBSD
 __attribute__((weak)) extern uint8_t __start___libfuzzer_extra_counters;
 __attribute__((weak)) extern uint8_t __stop___libfuzzer_extra_counters;
 
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/fuzzer/FuzzerExtFunctionsWeak.cpp
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/fuzzer/FuzzerExtFunctionsWeak.cpp
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/fuzzer/FuzzerExtFunctionsWeak.cpp
@@ -13,7 +13,7 @@
 //===----------------------------------------------------------------------===//
 #include "FuzzerDefs.h"
 #if LIBFUZZER_LINUX || LIBFUZZER_NETBSD || LIBFUZZER_FUCHSIA ||                \
-    LIBFUZZER_FREEBSD || LIBFUZZER_OPENBSD
+    LIBFUZZER_FREEBSD || LIBFUZZER_OPENBSD || LIBFUZZER_KFREEBSD
 
 #include "FuzzerExtFunctions.h"
 #include "FuzzerIO.h"
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/fuzzer/FuzzerUtilLinux.cpp
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/fuzzer/FuzzerUtilLinux.cpp
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/fuzzer/FuzzerUtilLinux.cpp
@@ -9,7 +9,7 @@
 //===----------------------------------------------------------------------===//
 #include "FuzzerDefs.h"
 #if LIBFUZZER_LINUX || LIBFUZZER_NETBSD || LIBFUZZER_FREEBSD ||                \
-    LIBFUZZER_OPENBSD
+    LIBFUZZER_OPENBSD || LIBFUZZER_KFREEBSD
 #include "FuzzerCommand.h"
 
 #include <stdlib.h>
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_freebsd.h
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/sanitizer_common/sanitizer_freebsd.h
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_freebsd.h
@@ -20,7 +20,7 @@
 // 32-bit mode.
 #if SANITIZER_FREEBSD && (SANITIZER_WORDSIZE == 32)
 # include <osreldate.h>
-# if __FreeBSD_version <= 902001  // v9.2
+# if !SANITIZER_KFREEBSD && __FreeBSD_version <= 902001 // v9.2
 #  include <link.h>
 #  include <sys/param.h>
 #  include <ucontext.h>
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_procmaps_bsd.cpp
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/sanitizer_common/sanitizer_procmaps_bsd.cpp
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_procmaps_bsd.cpp
@@ -37,7 +37,7 @@
 // Fix 'kinfo_vmentry' definition on FreeBSD prior v9.2 in 32-bit mode.
 #if SANITIZER_FREEBSD && (SANITIZER_WORDSIZE == 32)
 #include <osreldate.h>
-#if __FreeBSD_version <= 902001 // v9.2
+#if !SANITIZER_KFREEBSD && __FreeBSD_version <= 902001 // v9.2
 #define kinfo_vmentry xkinfo_vmentry
 #endif
 #endif
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.h
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.h
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.h
@@ -24,7 +24,9 @@
 #include "sanitizer_glibc_version.h"
 #endif
 
+#if !SANITIZER_KFREEBSD
 # define GET_LINK_MAP_BY_DLOPEN_HANDLE(handle) ((link_map*)(handle))
+#endif
 
 namespace __sanitizer {
 extern unsigned struct_utsname_sz;
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_syscall_generic.inc
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/sanitizer_common/sanitizer_syscall_generic.inc
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_syscall_generic.inc
@@ -19,7 +19,7 @@
 # define SYSCALL(name) __NR_ ## name
 #endif
 
-#if defined(__x86_64__) && (SANITIZER_FREEBSD || SANITIZER_MAC)
+#if defined(__x86_64__) && ((SANITIZER_FREEBSD  && !SANITIZER_KFREEBSD) || SANITIZER_MAC)
 # define internal_syscall __syscall
 # else
 # define internal_syscall syscall
Index: llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.cpp
===================================================================
--- llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3.orig/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.cpp
+++ llvm-toolchain-snapshot_10~+20191020075550+5b8546023f3/compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.cpp
@@ -109,10 +109,14 @@ typedef struct user_fpregs elf_fpregset_
 #include <wordexp.h>
 #endif
 
-#if SANITIZER_LINUX && !SANITIZER_ANDROID
+#if (SANITIZER_LINUX && !SANITIZER_ANDROID) || SANITIZER_KFREEBSD
 #include <glob.h>
 #include <obstack.h>
+#if SANITIZER_KFREEBSD
+#include <sys/mqueue.h>
+#else
 #include <mqueue.h>
+#endif
 #include <net/if_ppp.h>
 #include <netax25/ax25.h>
 #include <netipx/ipx.h>
@@ -150,8 +154,12 @@ typedef struct user_fpregs elf_fpregset_
 #include <linux/if_ppp.h>
 #endif
 
-#if SANITIZER_LINUX
+#if SANITIZER_LINUX || SANITIZER_KFREEBSD
+#if SANITIZER_KFREEBSD
+#include <sys/link.h>
+#else
 #include <link.h>
+#endif
 #include <sys/vfs.h>
 #include <sys/epoll.h>
 #include <linux/capability.h>