diff --git a/lib/libtsan/sanitizer_common/sanitizer_linux.cpp b/lib/libtsan/sanitizer_common/sanitizer_linux.cpp
index 16caf699a4..acb59dfd6b 100644
--- a/lib/libtsan/sanitizer_common/sanitizer_linux.cpp
+++ b/lib/libtsan/sanitizer_common/sanitizer_linux.cpp
@@ -174,8 +174,6 @@ const int FUTEX_WAKE_PRIVATE = FUTEX_WAKE | FUTEX_PRIVATE_FLAG;
 
 #  if SANITIZER_FREEBSD
 #    define SANITIZER_USE_GETENTROPY 1
-extern "C" void *__sys_mmap(void *addr, size_t len, int prot, int flags, int fd,
-                            off_t offset);
 #  endif
 
 namespace __sanitizer {
@@ -265,9 +263,8 @@ ScopedBlockSignals::~ScopedBlockSignals() { SetSigProcMask(&saved_, nullptr); }
 #    if !SANITIZER_S390
 uptr internal_mmap(void *addr, uptr length, int prot, int flags, int fd,
                    u64 offset) {
-#      if SANITIZER_FREEBSD
-  return (uptr)__sys_mmap(addr, length, prot, flags, fd, offset);
-#      elif SANITIZER_LINUX_USES_64BIT_SYSCALLS
+  /* zig patch: use direct syscall for freebsd mmap */
+#      if SANITIZER_FREEBSD || SANITIZER_LINUX_USES_64BIT_SYSCALLS
   return internal_syscall(SYSCALL(mmap), (uptr)addr, length, prot, flags, fd,
                           offset);
 #      else
@@ -942,6 +939,11 @@ int internal_fork() {
 }
 
 #    if SANITIZER_FREEBSD
+int internal_sigaction(int signum, const void *act, void *oldact) {
+  /* zig patch: use direct syscall for freebsd mmap */
+  return internal_syscall(SYSCALL(sigaction), signum, (uptr)act, (uptr)oldact);
+}
+
 int internal_sysctl(const int *name, unsigned int namelen, void *oldp,
                     uptr *oldlenp, const void *newp, uptr newlen) {
   return internal_syscall(SYSCALL(__sysctl), name, namelen, oldp,
diff --git a/lib/libtsan/sanitizer_common/sanitizer_linux_libcdep.cpp b/lib/libtsan/sanitizer_common/sanitizer_linux_libcdep.cpp
index f5cb85bc1b..1263f307ac 100644
--- a/lib/libtsan/sanitizer_common/sanitizer_linux_libcdep.cpp
+++ b/lib/libtsan/sanitizer_common/sanitizer_linux_libcdep.cpp
@@ -69,8 +69,6 @@
 #    undef MAP_NORESERVE
 #    define MAP_NORESERVE 0
 extern const Elf_Auxinfo *__elf_aux_vector __attribute__((weak));
-extern "C" int __sys_sigaction(int signum, const struct sigaction *act,
-                               struct sigaction *oldact);
 #  endif
 
 #  if SANITIZER_NETBSD
@@ -100,24 +98,17 @@ namespace __sanitizer {
 SANITIZER_WEAK_ATTRIBUTE int real_sigaction(int signum, const void *act,
                                             void *oldact);
 
+/* zig patch: use direct syscall for freebsd sigaction (sanitizer_linux.cpp) */
+#  if !SANITIZER_FREEBSD
 int internal_sigaction(int signum, const void *act, void *oldact) {
-#  if SANITIZER_FREEBSD
-  // On FreeBSD, call the sigaction syscall directly (part of libsys in FreeBSD
-  // 15) since the libc version goes via a global interposing table. Due to
-  // library initialization order the table can be relocated after the call to
-  // InitializeDeadlySignals() which then crashes when dereferencing the
-  // uninitialized pointer in libc.
-  return __sys_sigaction(signum, (const struct sigaction *)act,
-                         (struct sigaction *)oldact);
-#  else
 #    if !SANITIZER_GO
   if (&real_sigaction)
     return real_sigaction(signum, act, oldact);
 #    endif
   return sigaction(signum, (const struct sigaction *)act,
                    (struct sigaction *)oldact);
-#  endif
 }
+#  endif
 
 void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
                                 uptr *stack_bottom) {