diff --git a/libc/calls/dup-nt.c b/libc/calls/dup-nt.c
index b0bbec3cc..23887098f 100644
--- a/libc/calls/dup-nt.c
+++ b/libc/calls/dup-nt.c
@@ -61,7 +61,7 @@ textwindows int sys_dup_nt(int oldfd, int newfd, int flags, int start) {
   handle = g_fds.p[oldfd].handle;
   proc = GetCurrentProcess();
 
-  if (DuplicateHandle(proc, handle, proc, &g_fds.p[newfd].handle, 0, true,
+  if (DuplicateHandle(proc, handle, proc, &g_fds.p[newfd].handle, 0, false,
                       kNtDuplicateSameAccess)) {
     g_fds.p[newfd].kind = g_fds.p[oldfd].kind;
     g_fds.p[newfd].mode = g_fds.p[oldfd].mode;
diff --git a/libc/calls/execve-nt.greg.c b/libc/calls/execve-nt.greg.c
index e7535b32b..cb3ec3749 100644
--- a/libc/calls/execve-nt.greg.c
+++ b/libc/calls/execve-nt.greg.c
@@ -19,6 +19,7 @@
 #include "libc/calls/calls.h"
 #include "libc/calls/internal.h"
 #include "libc/calls/ntspawn.h"
+#include "libc/calls/struct/fd.internal.h"
 #include "libc/calls/struct/sigaction.internal.h"
 #include "libc/calls/syscall-nt.internal.h"
 #include "libc/dce.h"
@@ -37,6 +38,7 @@
 #include "libc/nt/enum/threadaccess.h"
 #include "libc/nt/enum/wait.h"
 #include "libc/nt/errors.h"
+#include "libc/nt/files.h"
 #include "libc/nt/memory.h"
 #include "libc/nt/process.h"
 #include "libc/nt/runtime.h"
@@ -65,6 +67,7 @@
 
 // clang-format off
 __msabi extern typeof(CloseHandle) *const __imp_CloseHandle;
+__msabi extern typeof(DuplicateHandle) *const __imp_DuplicateHandle;
 __msabi extern typeof(ExitProcess) *const __imp_ExitProcess;
 __msabi extern typeof(GenerateConsoleCtrlEvent) *const __imp_GenerateConsoleCtrlEvent;
 __msabi extern typeof(GetCurrentThreadId) *const __imp_GetCurrentThreadId;
@@ -72,6 +75,7 @@ __msabi extern typeof(GetExitCodeProcess) *const __imp_GetExitCodeProcess;
 __msabi extern typeof(GetLastError) *const __imp_GetLastError;
 __msabi extern typeof(OpenThread) *const __imp_OpenThread;
 __msabi extern typeof(SetConsoleCtrlHandler) *const __imp_SetConsoleCtrlHandler;
+__msabi extern typeof(SetHandleInformation) *const __imp_SetHandleInformation;
 __msabi extern typeof(TerminateThread) *const __imp_TerminateThread;
 __msabi extern typeof(UnmapViewOfFile) *const __imp_UnmapViewOfFile;
 __msabi extern typeof(WaitForSingleObject) *const __imp_WaitForSingleObject;
@@ -171,23 +175,6 @@ keywords int sys_execve_nt(const char *program, char *const argv[],
   PurgeThread(*_weaken(__sigchld_thread));
   PurgeThread(*_weaken(__sigwinch_thread));
 
-  // close win32 handles for memory mappings
-  // unlike fork calling execve destroys all memory
-  // closing a map handle won't impact the mapping itself
-  for (i = 0; i < _mmi.i; ++i) {
-    PurgeHandle(_mmi.p[i].h);
-  }
-
-  // close o_cloexec fds and anything that isn't stdio
-  for (i = 0; i < g_fds.n; ++i) {
-    if (g_fds.p[i].kind == kFdEmpty) {
-      g_fds.p[i].handle = -1;
-    } else if (i > 2 || (g_fds.p[i].flags & O_CLOEXEC)) {
-      PurgeHandle(g_fds.p[i].handle);
-      g_fds.p[i].handle = -1;
-    }
-  }
-
   // pass bitmask telling child which fds are sockets
   int bits;
   char buf[32], *v = 0;
@@ -205,10 +192,16 @@ keywords int sys_execve_nt(const char *program, char *const argv[],
   struct NtStartupInfo si = {
       .cb = sizeof(struct NtStartupInfo),
       .dwFlags = kNtStartfUsestdhandles,
-      .hStdInput = g_fds.p[0].handle,
-      .hStdOutput = g_fds.p[1].handle,
-      .hStdError = g_fds.p[2].handle,
   };
+  for (i = 0; i <= 2; ++i) {
+    if (g_fds.p[i].kind != kFdEmpty &&  //
+        !(g_fds.p[i].flags & O_CLOEXEC)) {
+      __imp_SetHandleInformation(g_fds.p[i].handle, kNtHandleFlagInherit, true);
+      si.stdiofds[i] = g_fds.p[i].handle;
+    } else {
+      si.stdiofds[i] = -1;
+    }
+  }
 
   // launch the process
   struct NtProcessInformation pi;
@@ -223,6 +216,11 @@ keywords int sys_execve_nt(const char *program, char *const argv[],
   }
   PurgeHandle(pi.hThread);
 
+  // remove duplicate handles
+  for (i = 0; i <= 2; ++i) {
+    PurgeHandle(si.stdiofds[i]);
+  }
+
   // retreat to original win32-provided stack memory
   __switch_stacks(pi.hProcess, 0, 0, 0, sys_execve_nt_relay, __oldstack);
 }
@@ -240,19 +238,25 @@ static keywords void sys_execve_nt_relay(intptr_t h, long b, long c, long d) {
 
   // close more handles
   __imp_SetConsoleCtrlHandler((void *)sys_execve_nt_event, 1);
-  PurgeThread(g_fds.stdin.thread);  // wasn't inherited by ntspawn
-  PurgeHandle(g_fds.stdin.reader);  // wasn't inherited by ntspawn
-  PurgeHandle(g_fds.stdin.writer);  // wasn't inherited by ntspawn
-  PurgeHandle(g_fds.p[0].handle);   // was inherited via startinfo
-  PurgeHandle(g_fds.p[1].handle);   // was inherited via startinfo
-  PurgeHandle(g_fds.p[2].handle);   // was inherited via startinfo
+  PurgeThread(g_fds.stdin.thread);
+  PurgeHandle(g_fds.stdin.reader);
+  PurgeHandle(g_fds.stdin.writer);
+  for (i = 0; i < g_fds.n; ++i) {
+    if (g_fds.p[i].kind != kFdEmpty) {
+      PurgeHandle(g_fds.p[i].handle);
+      if (g_fds.p[i].kind == kFdConsole) {
+        PurgeHandle(g_fds.p[i].extra);
+      }
+    }
+  }
   if (_weaken(__klog_handle)) {
-    PurgeHandle(*_weaken(__klog_handle));  // wasn't inherited by ntspawn
+    PurgeHandle(*_weaken(__klog_handle));
   }
 
   // free all the memory mmap created
   for (i = 0; i < _mmi.i; ++i) {
     __imp_UnmapViewOfFile((void *)((uintptr_t)_mmi.p[i].x << 16));
+    PurgeHandle(_mmi.p[i].h);
   }
 
   // wait for process to terminate
diff --git a/libc/calls/open-nt.c b/libc/calls/open-nt.c
index df5314a4a..70939298c 100644
--- a/libc/calls/open-nt.c
+++ b/libc/calls/open-nt.c
@@ -130,12 +130,11 @@ static textwindows int64_t sys_open_nt_impl(int dirfd, const char *path,
 
   // open the file, following symlinks
   int e = errno;
-  int64_t hand = CreateFile(path16, perm | extra_perm, share, &kNtIsInheritable,
-                            disp, attr | extra_attr, 0);
+  int64_t hand = CreateFile(path16, perm | extra_perm, share, 0, disp,
+                            attr | extra_attr, 0);
   if (hand == -1 && errno == EACCES && (flags & O_ACCMODE) == O_RDONLY) {
     errno = e;
-    hand = CreateFile(path16, perm, share, &kNtIsInheritable, disp,
-                      attr | extra_attr, 0);
+    hand = CreateFile(path16, perm, share, 0, disp, attr | extra_attr, 0);
   }
 
   return __fix_enotdir(hand, path16);
diff --git a/libc/calls/pipe-nt.c b/libc/calls/pipe-nt.c
index 1321343ef..f40d48657 100644
--- a/libc/calls/pipe-nt.c
+++ b/libc/calls/pipe-nt.c
@@ -19,6 +19,7 @@
 #include "libc/calls/internal.h"
 #include "libc/calls/state.internal.h"
 #include "libc/calls/syscall_support-nt.internal.h"
+#include "libc/intrin/handlock.internal.h"
 #include "libc/nt/createfile.h"
 #include "libc/nt/enum/accessmask.h"
 #include "libc/nt/enum/creationdisposition.h"
@@ -52,11 +53,11 @@ textwindows int sys_pipe_nt(int pipefd[2], unsigned flags) {
   }
   __fds_unlock();
   hin = CreateNamedPipe(pipename, kNtPipeAccessInbound | kNtFileFlagOverlapped,
-                        mode, 1, PIPE_BUF, PIPE_BUF, 0, &kNtIsInheritable);
+                        mode, 1, PIPE_BUF, PIPE_BUF, 0, 0);
   __fds_lock();
   if (hin != -1) {
-    if ((hout = CreateFile(pipename, kNtGenericWrite, 0, &kNtIsInheritable,
-                           kNtOpenExisting, kNtFileFlagOverlapped, 0)) != -1) {
+    if ((hout = CreateFile(pipename, kNtGenericWrite, 0, 0, kNtOpenExisting,
+                           kNtFileFlagOverlapped, 0)) != -1) {
       g_fds.p[reader].kind = kFdFile;
       g_fds.p[reader].flags = O_RDONLY | flags;
       g_fds.p[reader].mode = 0010444;
diff --git a/libc/calls/statfs-nt.c b/libc/calls/statfs-nt.c
index 4b656416d..bc78dadcb 100644
--- a/libc/calls/statfs-nt.c
+++ b/libc/calls/statfs-nt.c
@@ -33,8 +33,8 @@ textwindows int sys_statfs_nt(const char *path, struct statfs *sf) {
   if (__mkntpath(path, path16) == -1) return -1;
   h = __fix_enotdir(
       CreateFile(path16, kNtFileGenericRead,
-                 kNtFileShareRead | kNtFileShareWrite | kNtFileShareDelete,
-                 &kNtIsInheritable, kNtOpenExisting,
+                 kNtFileShareRead | kNtFileShareWrite | kNtFileShareDelete, 0,
+                 kNtOpenExisting,
                  kNtFileAttributeNormal | kNtFileFlagBackupSemantics, 0),
       path16);
   if (h == -1) return -1;
diff --git a/libc/intrin/__getauxval.c b/libc/intrin/__getauxval.c
index 312f3e4c0..38c81128c 100644
--- a/libc/intrin/__getauxval.c
+++ b/libc/intrin/__getauxval.c
@@ -28,7 +28,7 @@
  * @see System Five Application Binary Interface § 3.4.3
  * @asyncsignalsafe
  */
-dontasan struct AuxiliaryValue __getauxval(unsigned long at) {
+struct AuxiliaryValue __getauxval(unsigned long at) {
   unsigned long *ap;
   for (ap = __auxv; ap[0]; ap += 2) {
     if (at == ap[0]) {
diff --git a/libc/intrin/__getenv.c b/libc/intrin/__getenv.c
index c5a6d02b1..2610347ac 100644
--- a/libc/intrin/__getenv.c
+++ b/libc/intrin/__getenv.c
@@ -22,7 +22,7 @@
 #define ToUpper(c) \
   (IsWindows() && (c) >= 'a' && (c) <= 'z' ? (c) - 'a' + 'A' : (c))
 
-dontasan privileged struct Env __getenv(char **p, const char *k) {
+privileged struct Env __getenv(char **p, const char *k) {
   char *t;
   int i, j;
   for (i = 0; (t = p[i]); ++i) {
diff --git a/libc/intrin/asan.c b/libc/intrin/asan.c
index 9509c9f71..0cf16d802 100644
--- a/libc/intrin/asan.c
+++ b/libc/intrin/asan.c
@@ -773,7 +773,7 @@ static void __asan_report_memory_origin_image(intptr_t a, int z) {
   }
 }
 
-static dontasan void __asan_onmemory(void *x, void *y, size_t n, void *a) {
+static void __asan_onmemory(void *x, void *y, size_t n, void *a) {
   const unsigned char *p = x;
   struct ReportOriginHeap *t = a;
   if ((p <= t->a && t->a < p + n) ||
diff --git a/libc/intrin/describebacktrace.c b/libc/intrin/describebacktrace.c
index 444b48a39..fbf70a66f 100644
--- a/libc/intrin/describebacktrace.c
+++ b/libc/intrin/describebacktrace.c
@@ -25,8 +25,8 @@
 
 #define append(...) o += ksnprintf(buf + o, N - o, __VA_ARGS__)
 
-dontinstrument dontasan const char *(DescribeBacktrace)(char buf[N],
-                                                        struct StackFrame *fr) {
+dontinstrument const char *(DescribeBacktrace)(char buf[N],
+                                               struct StackFrame *fr) {
   bool gotsome = false;
   char *p = buf;
   char *pe = p + N;
diff --git a/libc/intrin/describentsecurityattributes.c b/libc/intrin/describentsecurityattributes.c
index 601c37500..e4eeb191a 100644
--- a/libc/intrin/describentsecurityattributes.c
+++ b/libc/intrin/describentsecurityattributes.c
@@ -24,7 +24,6 @@
 const char *(
     DescribeNtSecurityAttributes)(char buf[32],
                                   const struct NtSecurityAttributes *p) {
-  if (p == &kNtIsInheritable) return "&kNtIsInheritable";
   FormatInt64(buf, (uintptr_t)p);
   return buf;
 }
diff --git a/libc/intrin/directmap-metal.c b/libc/intrin/directmap-metal.c
index 463ac7637..61f9af589 100644
--- a/libc/intrin/directmap-metal.c
+++ b/libc/intrin/directmap-metal.c
@@ -32,15 +32,15 @@
 
 static uint64_t sys_mmap_metal_break;
 
-dontasan static struct DirectMap bad_mmap(void) {
+static struct DirectMap bad_mmap(void) {
   struct DirectMap res;
   res.addr = (void *)-1;
   res.maphandle = -1;
   return res;
 }
 
-dontasan struct DirectMap sys_mmap_metal(void *vaddr, size_t size, int prot,
-                                         int flags, int fd, int64_t off) {
+struct DirectMap sys_mmap_metal(void *vaddr, size_t size, int prot, int flags,
+                                int fd, int64_t off) {
   /* asan runtime depends on this function */
   size_t i;
   struct mman *mm;
diff --git a/libc/intrin/directmap-nt.c b/libc/intrin/directmap-nt.c
index d7c91d98f..0261dd904 100644
--- a/libc/intrin/directmap-nt.c
+++ b/libc/intrin/directmap-nt.c
@@ -42,13 +42,6 @@ textwindows struct DirectMap sys_mmap_nt(void *addr, size_t size, int prot,
     handle = g_fds.p[fd].handle;
   }
 
-  const struct NtSecurityAttributes *sec;
-  if ((flags & MAP_TYPE) != MAP_SHARED) {
-    sec = 0;  // MAP_PRIVATE isn't inherited across fork()
-  } else {
-    sec = &kNtIsInheritable;  // MAP_SHARED gives us zero-copy fork()
-  }
-
   // nt will whine under many circumstances if we change the execute bit
   // later using mprotect(). the workaround is to always request execute
   // and then virtualprotect() it away until we actually need it. please
@@ -80,7 +73,7 @@ textwindows struct DirectMap sys_mmap_nt(void *addr, size_t size, int prot,
   int e = errno;
   struct DirectMap dm;
 TryAgain:
-  if ((dm.maphandle = CreateFileMapping(handle, sec, fl.flags1,
+  if ((dm.maphandle = CreateFileMapping(handle, 0, fl.flags1,
                                         (size + off) >> 32, (size + off), 0))) {
     if ((dm.addr = MapViewOfFileEx(dm.maphandle, fl.flags2, off >> 32, off,
                                    size, addr))) {
diff --git a/libc/intrin/extend.c b/libc/intrin/extend.c
index ac3e4a635..a6ca27f69 100644
--- a/libc/intrin/extend.c
+++ b/libc/intrin/extend.c
@@ -32,7 +32,7 @@
 
 #define G FRAMESIZE
 
-static dontasan void *_mapframe(void *p, int f) {
+static void *_mapframe(void *p, int f) {
   int rc, prot, flags;
   struct DirectMap dm;
   prot = PROT_READ | PROT_WRITE;
@@ -73,7 +73,7 @@ static dontasan void *_mapframe(void *p, int f) {
  * @return new value for `e` or null w/ errno
  * @raise ENOMEM if we require more vespene gas
  */
-dontasan void *_extend(void *p, size_t n, void *e, int f, intptr_t h) {
+void *_extend(void *p, size_t n, void *e, int f, intptr_t h) {
   char *q;
   unassert(!((uintptr_t)SHADOW(p) & (G - 1)));
   unassert((uintptr_t)p + (G << kAsanScale) <= h);
diff --git a/libc/intrin/findmemoryinterval.c b/libc/intrin/findmemoryinterval.c
index 60e089bae..97cd261aa 100644
--- a/libc/intrin/findmemoryinterval.c
+++ b/libc/intrin/findmemoryinterval.c
@@ -18,7 +18,7 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #include "libc/runtime/memtrack.internal.h"
 
-dontasan unsigned __find_memory(const struct MemoryIntervals *mm, int x) {
+unsigned __find_memory(const struct MemoryIntervals *mm, int x) {
   unsigned l, m, r;
   l = 0;
   r = mm->i;
diff --git a/libc/intrin/ftrace_enabled.c b/libc/intrin/ftrace_enabled.c
index 287c20245..1e448fbe6 100644
--- a/libc/intrin/ftrace_enabled.c
+++ b/libc/intrin/ftrace_enabled.c
@@ -25,7 +25,7 @@
  * @param delta is added to enabled state
  * @return enabled state before `delta` was applied
  */
-dontasan dontubsan dontinstrument int ftrace_enabled(int delta) {
+dontinstrument int ftrace_enabled(int delta) {
   int res;
   struct CosmoTib *tib;
   if (__tls_enabled) {
diff --git a/libc/intrin/getpid.c b/libc/intrin/getpid.c
index 128a173bd..94b0fb4f1 100644
--- a/libc/intrin/getpid.c
+++ b/libc/intrin/getpid.c
@@ -41,7 +41,7 @@
  * @threadsafe
  * @vforksafe
  */
-dontasan int getpid(void) {
+int getpid(void) {
   int rc;
   if (IsMetal()) {
     rc = 1;
diff --git a/libc/intrin/handlock.c b/libc/intrin/handlock.c
new file mode 100644
index 000000000..742ea4ad6
--- /dev/null
+++ b/libc/intrin/handlock.c
@@ -0,0 +1,62 @@
+/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
+│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8                                :vi│
+╞══════════════════════════════════════════════════════════════════════════════╡
+│ Copyright 2023 Justine Alexandra Roberts Tunney                              │
+│                                                                              │
+│ Permission to use, copy, modify, and/or distribute this software for         │
+│ any purpose with or without fee is hereby granted, provided that the         │
+│ above copyright notice and this permission notice appear in all copies.      │
+│                                                                              │
+│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL                │
+│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED                │
+│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE             │
+│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL         │
+│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR        │
+│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER               │
+│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR             │
+│ PERFORMANCE OF THIS SOFTWARE.                                                │
+╚─────────────────────────────────────────────────────────────────────────────*/
+#include "libc/dce.h"
+#include "libc/intrin/weaken.h"
+#include "libc/str/str.h"
+#include "libc/thread/tls.h"
+#include "third_party/nsync/mu.h"
+
+/**
+ * @fileoverview r/w lock for maanging windows file inheritence
+ */
+
+static nsync_mu __hand_mu;
+
+void __hand_init(void) {
+  if (!SupportsWindows()) return;
+  bzero(&__hand_mu, sizeof(__hand_mu));
+}
+
+void __hand_rlock(void) {
+  if (!IsWindows()) return;
+  if (_weaken(nsync_mu_rlock) && __threaded) {
+    _weaken(nsync_mu_rlock)(&__hand_mu);
+  }
+}
+
+void __hand_runlock(void) {
+  if (!IsWindows()) return;
+  if (_weaken(nsync_mu_runlock) && __threaded) {
+    _weaken(nsync_mu_runlock)(&__hand_mu);
+  }
+}
+
+void __hand_lock(void) {
+  if (!IsWindows()) return;
+  if (_weaken(nsync_mu_lock) && __threaded) {
+    _weaken(nsync_mu_lock)(&__hand_mu);
+  }
+}
+
+void __hand_unlock(void) {
+  if (!IsWindows()) return;
+  if (_weaken(nsync_mu_unlock) && __threaded) {
+    _weaken(nsync_mu_unlock)(&__hand_mu);
+  }
+}
diff --git a/libc/intrin/handlock.internal.h b/libc/intrin/handlock.internal.h
new file mode 100644
index 000000000..b66405d2d
--- /dev/null
+++ b/libc/intrin/handlock.internal.h
@@ -0,0 +1,14 @@
+#ifndef COSMOPOLITAN_LIBC_INTRIN_HANDLOCK_INTERNAL_H_
+#define COSMOPOLITAN_LIBC_INTRIN_HANDLOCK_INTERNAL_H_
+#if !(__ASSEMBLER__ + __LINKER__ + 0)
+COSMOPOLITAN_C_START_
+
+void __hand_init(void);
+void __hand_rlock(void);
+void __hand_runlock(void);
+void __hand_lock(void);
+void __hand_unlock(void);
+
+COSMOPOLITAN_C_END_
+#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
+#endif /* COSMOPOLITAN_LIBC_INTRIN_HANDLOCK_INTERNAL_H_ */
diff --git a/libc/intrin/intrin.mk b/libc/intrin/intrin.mk
index 373d6fd13..d2181541b 100644
--- a/libc/intrin/intrin.mk
+++ b/libc/intrin/intrin.mk
@@ -46,31 +46,11 @@ $(LIBC_INTRIN_A).pkg:					\
 		$(LIBC_INTRIN_A_OBJS)			\
 		$(foreach x,$(LIBC_INTRIN_A_DIRECTDEPS),$($(x)_A).pkg)
 
-# we can't use asan because:
-#   __strace_init() calls this before asan is initialized
-o/$(MODE)/libc/intrin/strace_enabled.o: private		\
-		COPTS +=				\
-			-fno-sanitize=address
+o/$(MODE)/libc/intrin/mman.greg.o: private COPTS += -Os
 
-# we can't use asan because:
-#   asan guard pages haven't been allocated yet
-o/$(MODE)/libc/intrin/directmap.o			\
-o/$(MODE)/libc/intrin/directmap-nt.o: private		\
-		COPTS +=				\
-			-ffreestanding			\
-			-fno-sanitize=address
-
-# we want small code size because:
-#   to keep .text.head under 4096 bytes
-o/$(MODE)/libc/intrin/mman.greg.o: private		\
-		COPTS +=				\
-			-Os
-
-# we can't use asan and ubsan because:
-#   this is asan and ubsan
-o/$(MODE)/libc/intrin/asan.o				\
-o/$(MODE)/libc/intrin/ubsan.o: private			\
+$(LIBC_INTRIN_A_OBJS): private				\
 		CFLAGS +=				\
+			-x-no-pg			\
 			-ffreestanding			\
 			-fno-sanitize=all		\
 			-fno-stack-protector
@@ -81,121 +61,6 @@ o/$(MODE)/libc/intrin/asan.o: private			\
 			-finline			\
 			-finline-functions
 
-o/$(MODE)/libc/intrin/asanthunk.o: private		\
-		CFLAGS +=				\
-			-x-no-pg			\
-			-ffreestanding			\
-			-fno-sanitize=all		\
-			-fno-stack-protector
-
-# we can't use compiler magic because:
-#   kprintf() is mission critical to error reporting
-o/$(MODE)/libc/intrin/getmagnumstr.greg.o		\
-o/$(MODE)/libc/intrin/strerrno.greg.o			\
-o/$(MODE)/libc/intrin/strerrdoc.greg.o			\
-o/$(MODE)/libc/intrin/strerror_wr.greg.o		\
-o/$(MODE)/libc/intrin/kprintf.greg.o: private		\
-		CFLAGS +=				\
-			-fpie				\
-			-fwrapv				\
-			-x-no-pg			\
-			-ffreestanding			\
-			-fno-sanitize=all		\
-			-fno-stack-protector
-
-# TODO(jart): Do we really need these?
-# synchronization primitives are intended to be magic free
-o/$(MODE)/libc/intrin/futex_wait.o			\
-o/$(MODE)/libc/intrin/futex_wake.o			\
-o/$(MODE)/libc/intrin/gettid.greg.o			\
-o/$(MODE)/libc/intrin/_trylock_debug_4.o		\
-o/$(MODE)/libc/intrin/_spinlock_debug_4.o: private	\
-		CFLAGS +=				\
-			-fwrapv				\
-			-x-no-pg			\
-			-ffreestanding			\
-			-fno-sanitize=all		\
-			-mgeneral-regs-only		\
-			-fno-stack-protector
-
-# we can't use asan because:
-#   global gone could be raised
-o/$(MODE)/libc/intrin/exit.o				\
-o/$(MODE)/libc/intrin/restorewintty.o: private		\
-		CFLAGS +=				\
-			-fno-sanitize=all
-
-# we can't use -ftrapv because:
-#   this file implements it
-o/$(MODE)/libc/intrin/ftrapv.o: private			\
-		CFLAGS +=				\
-			-ffunction-sections		\
-			-ffreestanding			\
-			-fwrapv
-
-# we can't use asan because:
-#   sys_mmap() calls these which sets up shadow memory
-o/$(MODE)/libc/intrin/describeflags.o			\
-o/$(MODE)/libc/intrin/describeframe.o			\
-o/$(MODE)/libc/intrin/describemapflags.o		\
-o/$(MODE)/libc/intrin/describeprotflags.o: private	\
-		CFLAGS +=				\
-			-fno-sanitize=address
-
-o/$(MODE)/libc/intrin/exit1.greg.o			\
-o/$(MODE)/libc/intrin/wsarecv.o				\
-o/$(MODE)/libc/intrin/wsarecvfrom.o			\
-o/$(MODE)/libc/intrin/createfile.o			\
-o/$(MODE)/libc/intrin/reopenfile.o			\
-o/$(MODE)/libc/intrin/deletefile.o			\
-o/$(MODE)/libc/intrin/createpipe.o			\
-o/$(MODE)/libc/intrin/closehandle.o			\
-o/$(MODE)/libc/intrin/openprocess.o			\
-o/$(MODE)/libc/intrin/createthread.o			\
-o/$(MODE)/libc/intrin/findclose.o			\
-o/$(MODE)/libc/intrin/findnextfile.o			\
-o/$(MODE)/libc/intrin/createprocess.o			\
-o/$(MODE)/libc/intrin/findfirstfile.o			\
-o/$(MODE)/libc/intrin/removedirectory.o			\
-o/$(MODE)/libc/intrin/createsymboliclink.o		\
-o/$(MODE)/libc/intrin/createnamedpipe.o			\
-o/$(MODE)/libc/intrin/unmapviewoffile.o			\
-o/$(MODE)/libc/intrin/virtualprotect.o			\
-o/$(MODE)/libc/intrin/flushviewoffile.o			\
-o/$(MODE)/libc/intrin/createdirectory.o			\
-o/$(MODE)/libc/intrin/flushfilebuffers.o		\
-o/$(MODE)/libc/intrin/terminateprocess.o		\
-o/$(MODE)/libc/intrin/getfileattributes.o		\
-o/$(MODE)/libc/intrin/getexitcodeprocess.o		\
-o/$(MODE)/libc/intrin/waitforsingleobject.o		\
-o/$(MODE)/libc/intrin/setcurrentdirectory.o		\
-o/$(MODE)/libc/intrin/mapviewoffileex.o			\
-o/$(MODE)/libc/intrin/movefileex.o			\
-o/$(MODE)/libc/intrin/mapviewoffileexnuma.o		\
-o/$(MODE)/libc/intrin/createfilemapping.o		\
-o/$(MODE)/libc/intrin/createfilemappingnuma.o		\
-o/$(MODE)/libc/intrin/waitformultipleobjects.o		\
-o/$(MODE)/libc/intrin/wsagetoverlappedresult.o		\
-o/$(MODE)/libc/intrin/generateconsolectrlevent.o	\
-o/$(MODE)/libc/intrin/wsawaitformultipleevents.o: private\
-		CFLAGS +=				\
-			-Os				\
-			-fwrapv				\
-			-ffreestanding			\
-			-fno-stack-protector		\
-			-fno-sanitize=all
-
-# privileged functions
-o/$(MODE)/libc/intrin/dos2errno.o			\
-o/$(MODE)/libc/intrin/have_fsgsbase.o			\
-o/$(MODE)/libc/intrin/getmagnumstr.o			\
-o/$(MODE)/libc/intrin/formatint32.o			\
-o/$(MODE)/libc/intrin/strsignal_r.o			\
-o/$(MODE)/libc/intrin/strerror_wr.o: private		\
-		CFLAGS +=				\
-			-ffreestanding			\
-			-fno-sanitize=all
-
 o//libc/intrin/memmove.o: private			\
 		CFLAGS +=				\
 			-fno-toplevel-reorder
diff --git a/libc/intrin/isdebuggerpresent.c b/libc/intrin/isdebuggerpresent.c
index bbb48840f..96ecf5ec0 100644
--- a/libc/intrin/isdebuggerpresent.c
+++ b/libc/intrin/isdebuggerpresent.c
@@ -32,7 +32,7 @@
 #define kBufSize 1024
 #define kPid     "TracerPid:\t"
 
-static textwindows dontasan bool IsBeingDebugged(void) {
+static textwindows bool IsBeingDebugged(void) {
   return !!NtGetPeb()->BeingDebugged;
 }
 
diff --git a/libc/intrin/memchr.c b/libc/intrin/memchr.c
index db81b498d..4b98db885 100644
--- a/libc/intrin/memchr.c
+++ b/libc/intrin/memchr.c
@@ -36,9 +36,8 @@ static inline const unsigned char *memchr_pure(const unsigned char *s,
 }
 
 #if defined(__x86_64__) && !defined(__chibicc__)
-dontasan static inline const unsigned char *memchr_sse(const unsigned char *s,
-                                                       unsigned char c,
-                                                       size_t n) {
+static inline const unsigned char *memchr_sse(const unsigned char *s,
+                                              unsigned char c, size_t n) {
   size_t i;
   unsigned m;
   xmm_t v, t = {c, c, c, c, c, c, c, c, c, c, c, c, c, c, c, c};
@@ -68,7 +67,7 @@ dontasan static inline const unsigned char *memchr_sse(const unsigned char *s,
  * @return is pointer to first instance of c or NULL if not found
  * @asyncsignalsafe
  */
-dontasan void *memchr(const void *s, int c, size_t n) {
+void *memchr(const void *s, int c, size_t n) {
 #if defined(__x86_64__) && !defined(__chibicc__)
   const void *r;
   if (IsAsan()) __asan_verify(s, n);
diff --git a/libc/intrin/memrchr.c b/libc/intrin/memrchr.c
index f47f36bfc..aee1d67f5 100644
--- a/libc/intrin/memrchr.c
+++ b/libc/intrin/memrchr.c
@@ -37,9 +37,8 @@ static inline const unsigned char *memrchr_pure(const unsigned char *s,
 }
 
 #if defined(__x86_64__) && !defined(__chibicc__)
-dontasan static inline const unsigned char *memrchr_sse(const unsigned char *s,
-                                                        unsigned char c,
-                                                        size_t n) {
+static inline const unsigned char *memrchr_sse(const unsigned char *s,
+                                               unsigned char c, size_t n) {
   size_t i;
   unsigned m;
   xmm_t v, t = {c, c, c, c, c, c, c, c, c, c, c, c, c, c, c, c};
diff --git a/libc/intrin/mman.greg.c b/libc/intrin/mman.greg.c
index 1319b5d4f..f6f9ae3b6 100644
--- a/libc/intrin/mman.greg.c
+++ b/libc/intrin/mman.greg.c
@@ -54,7 +54,7 @@ struct ReclaimedPage {
 /**
  * Allocates new page of physical memory.
  */
-dontasan texthead uint64_t __new_page(struct mman *mm) {
+texthead uint64_t __new_page(struct mman *mm) {
   uint64_t p = mm->frp;
   if (p != NOPAGE) {
     uint64_t q;
@@ -81,8 +81,8 @@ dontasan texthead uint64_t __new_page(struct mman *mm) {
  * Returns pointer to page table entry for page at virtual address.
  * Additional page tables are allocated if needed as a side-effect.
  */
-dontasan textreal uint64_t *__get_virtual(struct mman *mm, uint64_t *t,
-                                          int64_t vaddr, bool maketables) {
+textreal uint64_t *__get_virtual(struct mman *mm, uint64_t *t, int64_t vaddr,
+                                 bool maketables) {
   uint64_t *e, p;
   unsigned char h;
   for (h = 39;; h -= 9) {
@@ -101,7 +101,7 @@ dontasan textreal uint64_t *__get_virtual(struct mman *mm, uint64_t *t,
 /**
  * Sorts, rounds, and filters BIOS memory map.
  */
-static dontasan textreal void __normalize_e820(struct mman *mm, uint64_t top) {
+static textreal void __normalize_e820(struct mman *mm, uint64_t top) {
   uint64_t a, b;
   uint64_t x, y;
   unsigned i, j, n;
@@ -134,10 +134,9 @@ static dontasan textreal void __normalize_e820(struct mman *mm, uint64_t top) {
 /**
  * Identity maps an area of physical memory to its negative address.
  */
-dontasan textreal uint64_t *__invert_memory_area(struct mman *mm,
-                                                 uint64_t *pml4t, uint64_t ps,
-                                                 uint64_t size,
-                                                 uint64_t pte_flags) {
+textreal uint64_t *__invert_memory_area(struct mman *mm, uint64_t *pml4t,
+                                        uint64_t ps, uint64_t size,
+                                        uint64_t pte_flags) {
   uint64_t pe = ps + size, p, *m = NULL;
   ps = ROUNDDOWN(ps, 4096);
   pe = ROUNDUP(pe, 4096);
@@ -153,7 +152,7 @@ dontasan textreal uint64_t *__invert_memory_area(struct mman *mm,
 /**
  * Increments the reference count for a page of physical memory.
  */
-dontasan void __ref_page(struct mman *mm, uint64_t *pml4t, uint64_t p) {
+void __ref_page(struct mman *mm, uint64_t *pml4t, uint64_t p) {
   uint64_t *m, e;
   m = __invert_memory_area(mm, pml4t, p, 4096, PAGE_RW | PAGE_XD);
   if (m) {
@@ -168,8 +167,7 @@ dontasan void __ref_page(struct mman *mm, uint64_t *pml4t, uint64_t p) {
 /**
  * Increments the reference counts for an area of physical memory.
  */
-dontasan void __ref_pages(struct mman *mm, uint64_t *pml4t, uint64_t ps,
-                          uint64_t size) {
+void __ref_pages(struct mman *mm, uint64_t *pml4t, uint64_t ps, uint64_t size) {
   uint64_t p = ROUNDDOWN(ps, 4096), e = ROUNDUP(ps + size, 4096);
   while (p != e) {
     __ref_page(mm, pml4t, p);
@@ -180,7 +178,7 @@ dontasan void __ref_pages(struct mman *mm, uint64_t *pml4t, uint64_t ps,
 /**
  * Reclaims a page of physical memory for later use.
  */
-static dontasan void __reclaim_page(struct mman *mm, uint64_t p) {
+static void __reclaim_page(struct mman *mm, uint64_t p) {
   struct ReclaimedPage *rp = (struct ReclaimedPage *)(BANE + p);
   unassert(p == (p & PAGE_TA));
   rp->next = mm->frp;
@@ -192,7 +190,7 @@ static dontasan void __reclaim_page(struct mman *mm, uint64_t p) {
  * page if there are no virtual addresses (excluding the negative space)
  * referring to it.
  */
-dontasan void __unref_page(struct mman *mm, uint64_t *pml4t, uint64_t p) {
+void __unref_page(struct mman *mm, uint64_t *pml4t, uint64_t p) {
   uint64_t *m, e;
   m = __invert_memory_area(mm, pml4t, p, 4096, PAGE_RW | PAGE_XD);
   if (m) {
@@ -208,8 +206,7 @@ dontasan void __unref_page(struct mman *mm, uint64_t *pml4t, uint64_t p) {
 /**
  * Identity maps all usable physical memory to its negative address.
  */
-static dontasan textreal void __invert_memory(struct mman *mm,
-                                              uint64_t *pml4t) {
+static textreal void __invert_memory(struct mman *mm, uint64_t *pml4t) {
   uint64_t i;
   for (i = 0; i < mm->e820n; ++i) {
     uint64_t ps = mm->e820[i].addr, size = mm->e820[i].size;
@@ -232,8 +229,7 @@ static dontasan textreal void __invert_memory(struct mman *mm,
                  : "i"(offsetof(type, member)));         \
   } while (0)
 
-dontasan textreal void __setup_mman(struct mman *mm, uint64_t *pml4t,
-                                    uint64_t top) {
+textreal void __setup_mman(struct mman *mm, uint64_t *pml4t, uint64_t top) {
   export_offsetof(struct mman, pc_drive_base_table);
   export_offsetof(struct mman, pc_drive_last_sector);
   export_offsetof(struct mman, pc_drive_last_head);
@@ -259,8 +255,8 @@ dontasan textreal void __setup_mman(struct mman *mm, uint64_t *pml4t,
 /**
  * Maps APE-defined ELF program headers into memory and clears BSS.
  */
-dontasan textreal void __map_phdrs(struct mman *mm, uint64_t *pml4t, uint64_t b,
-                                   uint64_t top) {
+textreal void __map_phdrs(struct mman *mm, uint64_t *pml4t, uint64_t b,
+                          uint64_t top) {
   uint64_t i, f, v, m;
   struct Elf64_Phdr *p;
   extern char ape_phdrs[] __attribute__((__weak__));
@@ -294,9 +290,8 @@ dontasan textreal void __map_phdrs(struct mman *mm, uint64_t *pml4t, uint64_t b,
  * Reclaims memory pages which were used at boot time but which can now be
  * made available for the application.
  */
-dontasan textreal void __reclaim_boot_pages(struct mman *mm,
-                                            uint64_t skip_start,
-                                            uint64_t skip_end) {
+textreal void __reclaim_boot_pages(struct mman *mm, uint64_t skip_start,
+                                   uint64_t skip_end) {
   uint64_t p = mm->frp, q = IMAGE_BASE_REAL, i, n = mm->e820n, b, e;
   for (i = 0; i < n; ++i) {
     b = mm->e820[i].addr;
diff --git a/libc/intrin/nocolor.c b/libc/intrin/nocolor.c
index 60ad3efa9..09109427f 100644
--- a/libc/intrin/nocolor.c
+++ b/libc/intrin/nocolor.c
@@ -48,9 +48,8 @@
  */
 bool __nocolor;
 
-optimizesize textstartup dontasan void __nocolor_init(int argc, char **argv,
-                                                      char **envp,
-                                                      intptr_t *auxv) {
+optimizesize textstartup void __nocolor_init(int argc, char **argv, char **envp,
+                                             intptr_t *auxv) {
   char *s;
   __nocolor = (IsWindows() && !IsAtLeastWindows10()) ||
               ((s = getenv("TERM")) && IsDumb(s));
diff --git a/libc/intrin/ntgetversion.c b/libc/intrin/ntgetversion.c
index 5b88bce1c..e57b09ca3 100644
--- a/libc/intrin/ntgetversion.c
+++ b/libc/intrin/ntgetversion.c
@@ -27,7 +27,7 @@
  *
  * @see IsAtLeastWindows10()
  */
-textwindows dontasan int NtGetVersion(void) {
+textwindows int NtGetVersion(void) {
   return (NtGetPeb()->OSMajorVersion & 0xff) << 8 | NtGetPeb()->OSMinorVersion;
 }
 
diff --git a/libc/intrin/stpcpy.c b/libc/intrin/stpcpy.c
index ba7b97a63..475dcdc2c 100644
--- a/libc/intrin/stpcpy.c
+++ b/libc/intrin/stpcpy.c
@@ -33,7 +33,7 @@ typedef char xmm_t __attribute__((__vector_size__(16), __aligned__(16)));
  * @return pointer to nul byte
  * @asyncsignalsafe
  */
-dontasan char *stpcpy(char *d, const char *s) {
+char *stpcpy(char *d, const char *s) {
   size_t i = 0;
   if (IsAsan()) {
     __asan_verify(d, strlen(s) + 1);
diff --git a/libc/intrin/strace.internal.h b/libc/intrin/strace.internal.h
index 55455e4bc..141b50308 100644
--- a/libc/intrin/strace.internal.h
+++ b/libc/intrin/strace.internal.h
@@ -4,11 +4,11 @@
 #include "libc/runtime/runtime.h"
 
 #define _KERNTRACE  0 /* not configurable w/ flag yet */
-#define _POLLTRACE  1 /* not configurable w/ flag yet */
+#define _POLLTRACE  0 /* not configurable w/ flag yet */
 #define _DATATRACE  1 /* not configurable w/ flag yet */
 #define _STDIOTRACE 0 /* not configurable w/ flag yet */
 #define _LOCKTRACE  0 /* not configurable w/ flag yet */
-#define _NTTRACE    1 /* not configurable w/ flag yet */
+#define _NTTRACE    0 /* not configurable w/ flag yet */
 
 #define STRACE_PROLOGUE "%rSYS %6P %'18T "
 
diff --git a/libc/intrin/strace_enabled.c b/libc/intrin/strace_enabled.c
index c5c42a1f1..e3783b36c 100644
--- a/libc/intrin/strace_enabled.c
+++ b/libc/intrin/strace_enabled.c
@@ -25,7 +25,7 @@
  * @param delta is added to enabled state
  * @return enabled state before `delta` was applied
  */
-dontasan dontubsan dontinstrument int strace_enabled(int delta) {
+dontinstrument int strace_enabled(int delta) {
   int res;
   struct CosmoTib *tib;
   if (__tls_enabled) {
diff --git a/libc/intrin/strchr.c b/libc/intrin/strchr.c
index 4651a4ffe..cfad794a9 100644
--- a/libc/intrin/strchr.c
+++ b/libc/intrin/strchr.c
@@ -32,7 +32,7 @@ static inline const char *strchr_pure(const char *s, int c) {
 
 #if defined(__x86_64__) && !defined(__chibicc__)
 typedef char xmm_t __attribute__((__vector_size__(16), __aligned__(16)));
-dontasan static inline const char *strchr_sse(const char *s, unsigned char c) {
+static inline const char *strchr_sse(const char *s, unsigned char c) {
   unsigned k;
   unsigned m;
   const xmm_t *p;
@@ -56,7 +56,7 @@ dontasan static inline const char *strchr_sse(const char *s, unsigned char c) {
 }
 #endif
 
-static dontasan inline const char *strchr_x64(const char *p, uint64_t c) {
+static inline const char *strchr_x64(const char *p, uint64_t c) {
   unsigned a, b;
   uint64_t w, x, y;
   for (c *= 0x0101010101010101;; p += 8) {
@@ -95,7 +95,7 @@ static dontasan inline const char *strchr_x64(const char *p, uint64_t c) {
  * @asyncsignalsafe
  * @vforksafe
  */
-dontasan char *strchr(const char *s, int c) {
+char *strchr(const char *s, int c) {
   if (IsAsan()) __asan_verify_str(s);
 #if defined(__x86_64__) && !defined(__chibicc__)
   const char *r;
diff --git a/libc/intrin/strchrnul.c b/libc/intrin/strchrnul.c
index 5ab232bda..1addf586c 100644
--- a/libc/intrin/strchrnul.c
+++ b/libc/intrin/strchrnul.c
@@ -32,8 +32,7 @@ static inline const char *strchrnul_pure(const char *s, int c) {
 
 #if defined(__x86_64__) && !defined(__chibicc__)
 typedef char xmm_t __attribute__((__vector_size__(16), __aligned__(16)));
-dontasan static inline const char *strchrnul_sse(const char *s,
-                                                 unsigned char c) {
+static inline const char *strchrnul_sse(const char *s, unsigned char c) {
   unsigned k;
   unsigned m;
   const xmm_t *p;
@@ -54,7 +53,7 @@ dontasan static inline const char *strchrnul_sse(const char *s,
 }
 #endif
 
-dontasan static const char *strchrnul_x64(const char *p, uint64_t c) {
+static const char *strchrnul_x64(const char *p, uint64_t c) {
   unsigned a, b;
   uint64_t w, x, y;
   for (c *= 0x0101010101010101;; p += 8) {
diff --git a/libc/intrin/strcmp.c b/libc/intrin/strcmp.c
index 8e085acdd..a6a164ee7 100644
--- a/libc/intrin/strcmp.c
+++ b/libc/intrin/strcmp.c
@@ -29,7 +29,7 @@
  * @return is <0, 0, or >0 based on uint8_t comparison
  * @asyncsignalsafe
  */
-dontasan int strcmp(const char *a, const char *b) {
+int strcmp(const char *a, const char *b) {
   int c;
   size_t i = 0;
   uint64_t v, w;
diff --git a/libc/intrin/strcpy.c b/libc/intrin/strcpy.c
index ad5986fed..5176c47a1 100644
--- a/libc/intrin/strcpy.c
+++ b/libc/intrin/strcpy.c
@@ -33,7 +33,7 @@ typedef char xmm_t __attribute__((__vector_size__(16), __aligned__(16)));
  * @return original dest
  * @asyncsignalsafe
  */
-dontasan char *strcpy(char *d, const char *s) {
+char *strcpy(char *d, const char *s) {
   size_t i = 0;
   if (IsAsan()) {
     __asan_verify_str(s);
diff --git a/libc/intrin/strerror_r.c b/libc/intrin/strerror_r.c
index 77d91074a..0a22a8d6e 100644
--- a/libc/intrin/strerror_r.c
+++ b/libc/intrin/strerror_r.c
@@ -25,7 +25,7 @@
 // clang-format off
 
 #if defined(SYSDEBUG) && _NTTRACE
-dontasan dontubsan privileged
+privileged
 #endif
 
 /**
diff --git a/libc/intrin/strerror_wr.greg.c b/libc/intrin/strerror_wr.greg.c
index 38a98a9a2..df65d2f9f 100644
--- a/libc/intrin/strerror_wr.greg.c
+++ b/libc/intrin/strerror_wr.greg.c
@@ -30,7 +30,7 @@
 // clang-format off
 
 #if defined(SYSDEBUG) && _NTTRACE
-dontasan dontubsan privileged
+privileged
 #endif
 
 /**
diff --git a/libc/intrin/strlen.c b/libc/intrin/strlen.c
index 1b0f77433..9004a1949 100644
--- a/libc/intrin/strlen.c
+++ b/libc/intrin/strlen.c
@@ -28,7 +28,7 @@
  * @return number of bytes (excluding NUL)
  * @asyncsignalsafe
  */
-dontasan size_t strlen(const char *s) {
+size_t strlen(const char *s) {
   if (IsAsan()) __asan_verify_str(s);
 #if defined(__x86_64__) && !defined(__chibicc__)
   typedef char xmm_t __attribute__((__vector_size__(16), __aligned__(16)));
diff --git a/libc/intrin/strnlen.c b/libc/intrin/strnlen.c
index 02dd4aee4..f8bb64328 100644
--- a/libc/intrin/strnlen.c
+++ b/libc/intrin/strnlen.c
@@ -23,7 +23,7 @@
 #include "libc/str/str.h"
 #ifndef __aarch64__
 
-static dontasan size_t strnlen_x64(const char *s, size_t n, size_t i) {
+static size_t strnlen_x64(const char *s, size_t n, size_t i) {
   uint64_t w;
   for (; i + 8 < n; i += 8) {
     w = *(uint64_t *)(s + i);
@@ -43,7 +43,7 @@ static dontasan size_t strnlen_x64(const char *s, size_t n, size_t i) {
  * @return byte length
  * @asyncsignalsafe
  */
-dontasan size_t strnlen(const char *s, size_t n) {
+size_t strnlen(const char *s, size_t n) {
   size_t i;
   if (IsAsan() && n) __asan_verify(s, 1);
   for (i = 0; (uintptr_t)(s + i) & 7; ++i) {
diff --git a/libc/intrin/strrchr.c b/libc/intrin/strrchr.c
index 59a230c71..bcbbf34f3 100644
--- a/libc/intrin/strrchr.c
+++ b/libc/intrin/strrchr.c
@@ -31,6 +31,6 @@ char *strrchr(const char *s, int c) {
   return memrchr(s, c, strlen(s));
 }
 
-__strong_reference(strrchr, rindex);
+__weak_reference(strrchr, rindex);
 
 #endif /* __aarch64__ */
diff --git a/libc/runtime/fork-nt.c b/libc/runtime/fork-nt.c
index 845ccbda2..4caefa948 100644
--- a/libc/runtime/fork-nt.c
+++ b/libc/runtime/fork-nt.c
@@ -19,6 +19,7 @@
 #include "libc/calls/internal.h"
 #include "libc/calls/ntspawn.h"
 #include "libc/calls/state.internal.h"
+#include "libc/calls/struct/fd.internal.h"
 #include "libc/calls/syscall-nt.internal.h"
 #include "libc/calls/syscall_support-nt.internal.h"
 #include "libc/calls/wincrash.internal.h"
@@ -26,6 +27,7 @@
 #include "libc/fmt/itoa.h"
 #include "libc/intrin/atomic.h"
 #include "libc/intrin/directmap.internal.h"
+#include "libc/intrin/handlock.internal.h"
 #include "libc/intrin/kprintf.h"
 #include "libc/intrin/strace.internal.h"
 #include "libc/intrin/weaken.h"
@@ -43,6 +45,7 @@
 #include "libc/nt/enum/processcreationflags.h"
 #include "libc/nt/enum/startf.h"
 #include "libc/nt/errors.h"
+#include "libc/nt/files.h"
 #include "libc/nt/ipc.h"
 #include "libc/nt/memory.h"
 #include "libc/nt/process.h"
@@ -313,6 +316,21 @@ textwindows void WinMainForked(void) {
   longjmp(jb, 1);
 }
 
+static void __hand_inherit(bool32 bInherit) {
+  for (int i = 0; i < _mmi.i; ++i) {
+    if ((_mmi.p[i].flags & MAP_TYPE) == MAP_SHARED) {
+      SetHandleInformation(_mmi.p[i].h, kNtHandleFlagInherit, bInherit);
+    }
+  }
+  for (int i = 0; i < g_fds.n; ++i) {
+    if (g_fds.p[i].kind == kFdEmpty) continue;
+    SetHandleInformation(g_fds.p[i].handle, kNtHandleFlagInherit, bInherit);
+    if (g_fds.p[i].kind == kFdConsole) {
+      SetHandleInformation(g_fds.p[i].extra, kNtHandleFlagInherit, bInherit);
+    }
+  }
+}
+
 textwindows int sys_fork_nt(uint32_t dwCreationFlags) {
   jmp_buf jb;
   uint32_t op;
@@ -357,8 +375,12 @@ textwindows int sys_fork_nt(uint32_t dwCreationFlags) {
         args = args2;
       }
 #endif
-      if (ntspawn(GetProgramExecutableName(), args, environ, forkvar, 0, 0,
-                  true, dwCreationFlags, 0, &startinfo, &procinfo) != -1) {
+      __hand_inherit(true);
+      int spawnrc =
+          ntspawn(GetProgramExecutableName(), args, environ, forkvar, 0, 0,
+                  true, dwCreationFlags, 0, &startinfo, &procinfo);
+      __hand_inherit(false);
+      if (spawnrc != -1) {
         CloseHandle(procinfo.hThread);
         ok = WriteAll(writer, jb, sizeof(jb)) &&
              WriteAll(writer, &_mmi.i, sizeof(_mmi.i)) &&
diff --git a/libc/runtime/winmain.greg.c b/libc/runtime/winmain.greg.c
index f07723e8a..7d1325310 100644
--- a/libc/runtime/winmain.greg.c
+++ b/libc/runtime/winmain.greg.c
@@ -127,7 +127,7 @@ __msabi static textwindows void DeduplicateStdioHandles(void) {
       int64_t h2 = __imp_GetStdHandle(kNtStdio[j]);
       if (h1 == h2) {
         int64_t h3, proc = __imp_GetCurrentProcess();
-        __imp_DuplicateHandle(proc, h2, proc, &h3, 0, true,
+        __imp_DuplicateHandle(proc, h2, proc, &h3, 0, false,
                               kNtDuplicateSameAccess);
         __imp_SetStdHandle(kNtStdio[j], h3);
       }
@@ -159,11 +159,10 @@ __msabi static textwindows wontreturn void WinInit(const char16_t *cmdline) {
   _mmi.n = ARRAYLEN(_mmi.s);
   uintptr_t stackaddr = GetStaticStackAddr(0);
   size_t stacksize = GetStaticStackSize();
-  __imp_MapViewOfFileEx((_mmi.p[0].h = __imp_CreateFileMappingW(
-                             -1, &kNtIsInheritable, kNtPageExecuteReadwrite,
-                             stacksize >> 32, stacksize, NULL)),
-                        kNtFileMapWrite | kNtFileMapExecute, 0, 0, stacksize,
-                        (void *)stackaddr);
+  __imp_MapViewOfFileEx(
+      (_mmi.p[0].h = __imp_CreateFileMappingW(
+           -1, 0, kNtPageExecuteReadwrite, stacksize >> 32, stacksize, NULL)),
+      kNtFileMapWrite | kNtFileMapExecute, 0, 0, stacksize, (void *)stackaddr);
   int prot = (intptr_t)ape_stack_prot;
   if (~prot & PROT_EXEC) {
     uint32_t old;
@@ -186,9 +185,8 @@ __msabi static textwindows wontreturn void WinInit(const char16_t *cmdline) {
     uintptr_t shallocend = ROUNDUP(shadowend, FRAMESIZE);
     uintptr_t shallocsize = shallocend - shallocaddr;
     __imp_MapViewOfFileEx(
-        (_mmi.p[1].h =
-             __imp_CreateFileMappingW(-1, &kNtIsInheritable, kNtPageReadwrite,
-                                      shallocsize >> 32, shallocsize, NULL)),
+        (_mmi.p[1].h = __imp_CreateFileMappingW(
+             -1, 0, kNtPageReadwrite, shallocsize >> 32, shallocsize, NULL)),
         kNtFileMapWrite, 0, 0, shallocsize, (void *)shallocaddr);
     _mmi.p[1].x = shallocaddr >> 16;
     _mmi.p[1].y = (shallocaddr >> 16) + ((shallocsize - 1) >> 16);
diff --git a/libc/sock/socketpair-nt.c b/libc/sock/socketpair-nt.c
index c5180d5fc..dffeced49 100644
--- a/libc/sock/socketpair-nt.c
+++ b/libc/sock/socketpair-nt.c
@@ -64,16 +64,16 @@ textwindows int sys_socketpair_nt(int family, int type, int proto, int sv[2]) {
     if (writer != -1) __releasefd(writer);
     return -1;
   }
-  if ((hpipe = CreateNamedPipe(
-           pipename, kNtPipeAccessDuplex | kNtFileFlagOverlapped, mode, 1,
-           65536, 65536, 0, &kNtIsInheritable)) == -1) {
+  if ((hpipe = CreateNamedPipe(pipename,
+                               kNtPipeAccessDuplex | kNtFileFlagOverlapped,
+                               mode, 1, 65536, 65536, 0, 0)) == -1) {
     __releasefd(writer);
     __releasefd(reader);
     return -1;
   }
 
-  h1 = CreateFile(pipename, kNtGenericWrite | kNtGenericRead, 0,
-                  &kNtIsInheritable, kNtOpenExisting, kNtFileFlagOverlapped, 0);
+  h1 = CreateFile(pipename, kNtGenericWrite | kNtGenericRead, 0, 0,
+                  kNtOpenExisting, kNtFileFlagOverlapped, 0);
 
   __fds_lock();
 
diff --git a/libc/stdio/posix_spawn.c b/libc/stdio/posix_spawn.c
index 3ca50e6c7..bade9ef96 100644
--- a/libc/stdio/posix_spawn.c
+++ b/libc/stdio/posix_spawn.c
@@ -34,11 +34,13 @@
 #include "libc/fmt/magnumstrs.internal.h"
 #include "libc/intrin/asan.internal.h"
 #include "libc/intrin/describeflags.internal.h"
+#include "libc/intrin/handlock.internal.h"
 #include "libc/intrin/strace.internal.h"
 #include "libc/intrin/weaken.h"
 #include "libc/mem/alloca.h"
 #include "libc/nt/enum/processcreationflags.h"
 #include "libc/nt/enum/startf.h"
+#include "libc/nt/files.h"
 #include "libc/nt/runtime.h"
 #include "libc/nt/struct/processinformation.h"
 #include "libc/nt/struct/startupinfo.h"
@@ -66,6 +68,14 @@ static void posix_spawn_cleanup3fds(int fds[3]) {
   }
 }
 
+static void posix_spawn_inherit(int64_t hands[3], bool32 bInherit) {
+  for (int i = 0; i < 3; ++i) {
+    if (hands[i] != -1) {
+      SetHandleInformation(hands[i], kNtHandleFlagInherit, bInherit);
+    }
+  }
+}
+
 static const char *DescribePid(char buf[12], int err, int *pid) {
   if (err) return "n/a";
   if (!pid) return "NULL";
@@ -176,9 +186,13 @@ static textwindows errno_t posix_spawn_windows_impl(
   int rc, e = errno;
   struct NtProcessInformation procinfo;
   if (!envp) envp = environ;
+  __hand_rlock();
+  posix_spawn_inherit(stdio_handle, true);
   rc = ntspawn(path, argv, envp, v, 0, 0, bInheritHandles, dwCreationFlags, 0,
                &startinfo, &procinfo);
+  posix_spawn_inherit(stdio_handle, false);
   posix_spawn_cleanup3fds(close_this_fd_later);
+  __hand_runlock();
   if (rc == -1) {
     int err = errno;
     __releasefd(child);
diff --git a/libc/thread/pthread_atfork.c b/libc/thread/pthread_atfork.c
index ce6674ada..4ce0519fb 100644
--- a/libc/thread/pthread_atfork.c
+++ b/libc/thread/pthread_atfork.c
@@ -24,6 +24,7 @@
 #include "libc/errno.h"
 #include "libc/intrin/atomic.h"
 #include "libc/intrin/dll.h"
+#include "libc/intrin/handlock.internal.h"
 #include "libc/intrin/leaky.internal.h"
 #include "libc/mem/mem.h"
 #include "libc/runtime/memtrack.internal.h"
@@ -64,11 +65,13 @@ void _pthread_onfork_prepare(void) {
   _pthread_onfork(0);
   pthread_spin_lock(&_pthread_lock);
   __fds_lock();
+  __hand_lock();
   __mmi_lock();
 }
 
 void _pthread_onfork_parent(void) {
   __mmi_unlock();
+  __hand_unlock();
   __fds_unlock();
   pthread_spin_unlock(&_pthread_lock);
   _pthread_onfork(1);
@@ -87,6 +90,7 @@ void _pthread_onfork_child(void) {
   atomic_store_explicit(&pt->cancelled, false, memory_order_relaxed);
 
   // wipe core runtime locks
+  __hand_init();
   pthread_mutexattr_init(&attr);
   pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
   pthread_mutex_init(&__mmi_lock_obj, &attr);
diff --git a/test/libc/stdio/posix_spawn_test.c b/test/libc/stdio/posix_spawn_test.c
index ba149861f..390426d59 100644
--- a/test/libc/stdio/posix_spawn_test.c
+++ b/test/libc/stdio/posix_spawn_test.c
@@ -252,7 +252,7 @@ void PosixSpawnWait(const char *prog) {
 }
 
 BENCH(posix_spawn, bench) {
-  long n = 128L * 1000 * 1000;
+  long n = 1L * 1000 * 1000;
   memset(gc(malloc(n)), -1, n);
   creat("tiny64", 0755);
   write(3, kTinyLinuxExit, 128);
diff --git a/test/libc/intrin/pthread_atfork_test.c b/test/libc/thread/pthread_atfork_test.c
similarity index 100%
rename from test/libc/intrin/pthread_atfork_test.c
rename to test/libc/thread/pthread_atfork_test.c