diff --git a/libc/include/signal.h b/libc/include/signal.h
index 0159bf21c..c01b33a45 100644
--- a/libc/include/signal.h
+++ b/libc/include/signal.h
@@ -51,14 +51,15 @@ __BEGIN_DECLS
 
 typedef int sig_atomic_t;
 
-/* TODO: 64-bit: we should probably #undef the uapi NSIG and add a unit test that NSIG == _NSIG && NSIG >= 64. */
-#ifndef _NSIG
-#  define _NSIG 64
-#endif
-#ifndef NSIG
-#  define NSIG _NSIG
+/* The arm and x86 kernel header files don't define _NSIG. */
+#ifndef _KERNEL__NSIG
+#define _KERNEL__NSIG 64
 #endif
 
+/* Userspace's NSIG is the kernel's _NSIG + 1. */
+#define _NSIG (_KERNEL__NSIG + 1)
+#define NSIG _NSIG
+
 extern const char* const sys_siglist[];
 extern const char* const sys_signame[];
 
diff --git a/libc/kernel/tools/cpp.py b/libc/kernel/tools/cpp.py
index 04e42567c..2c40d7c60 100644
--- a/libc/kernel/tools/cpp.py
+++ b/libc/kernel/tools/cpp.py
@@ -1521,7 +1521,7 @@ class BlockList:
         """replace tokens according to the given dict
            """
         for b in self.blocks:
-            if not b.isDirective():
+            if (not b.isDirective()) or b.isDefine():
                 for tok in b.tokens:
                     if tok.id == tokIDENT:
                         if tok.value in replacements:
diff --git a/libc/kernel/tools/defaults.py b/libc/kernel/tools/defaults.py
index f2358033c..09556c9e6 100644
--- a/libc/kernel/tools/defaults.py
+++ b/libc/kernel/tools/defaults.py
@@ -57,10 +57,15 @@ kernel_arch_token_replacements = {
     "mips": {"off_t":"__kernel_off_t"},
     "x86": {},
     }
+
 # Replace tokens in the output according to this mapping
 kernel_token_replacements = {
     "asm": "__asm__",
-    "__unused": "__linux_unused", # The kernel usage of __unused conflicts with the macro defined in sys/cdefs.h
+    # The kernel usage of __unused for unused struct fields conflicts with the macro defined in <sys/cdefs.h>.
+    "__unused": "__linux_unused",
+    # The kernel's _NSIG/NSIG are one less than the userspace value, so we need to move them aside.
+    "_NSIG": "_KERNEL__NSIG",
+    "NSIG": "_KERNEL_NSIG",
     }
 
 # this is the set of known static inline functions that we want to keep
diff --git a/libc/kernel/uapi/asm-arm/asm/signal.h b/libc/kernel/uapi/asm-arm/asm/signal.h
index 9297a7003..512e22a25 100644
--- a/libc/kernel/uapi/asm-arm/asm/signal.h
+++ b/libc/kernel/uapi/asm-arm/asm/signal.h
@@ -21,7 +21,7 @@
 #include <linux/types.h>
 struct siginfo;
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
-#define NSIG 32
+#define _KERNEL_NSIG 32
 typedef unsigned long sigset_t;
 #define SIGHUP 1
 #define SIGINT 2
@@ -67,7 +67,7 @@ typedef unsigned long sigset_t;
 #define SIGUNUSED 31
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define SIGRTMIN 32
-#define SIGRTMAX _NSIG
+#define SIGRTMAX _KERNEL__NSIG
 #define SIGSWI 32
 #define SA_NOCLDSTOP 0x00000001
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
diff --git a/libc/kernel/uapi/asm-generic/signal.h b/libc/kernel/uapi/asm-generic/signal.h
index c4c7e00e4..fe7d9a097 100644
--- a/libc/kernel/uapi/asm-generic/signal.h
+++ b/libc/kernel/uapi/asm-generic/signal.h
@@ -19,10 +19,10 @@
 #ifndef _UAPI__ASM_GENERIC_SIGNAL_H
 #define _UAPI__ASM_GENERIC_SIGNAL_H
 #include <linux/types.h>
-#define _NSIG 64
+#define _KERNEL__NSIG 64
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define _NSIG_BPW __BITS_PER_LONG
-#define _NSIG_WORDS (_NSIG / _NSIG_BPW)
+#define _NSIG_WORDS (_KERNEL__NSIG / _NSIG_BPW)
 #define SIGHUP 1
 #define SIGINT 2
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
@@ -68,7 +68,7 @@
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define SIGRTMIN 32
 #ifndef SIGRTMAX
-#define SIGRTMAX _NSIG
+#define SIGRTMAX _KERNEL__NSIG
 #endif
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define SA_NOCLDSTOP 0x00000001
diff --git a/libc/kernel/uapi/asm-mips/asm/signal.h b/libc/kernel/uapi/asm-mips/asm/signal.h
index 771e31a6e..53f501513 100644
--- a/libc/kernel/uapi/asm-mips/asm/signal.h
+++ b/libc/kernel/uapi/asm-mips/asm/signal.h
@@ -19,10 +19,10 @@
 #ifndef _UAPI_ASM_SIGNAL_H
 #define _UAPI_ASM_SIGNAL_H
 #include <linux/types.h>
-#define _NSIG 128
+#define _KERNEL__NSIG 128
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define _NSIG_BPW (sizeof(unsigned long) * 8)
-#define _NSIG_WORDS (_NSIG / _NSIG_BPW)
+#define _NSIG_WORDS (_KERNEL__NSIG / _NSIG_BPW)
 typedef struct {
  unsigned long sig[_NSIG_WORDS];
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
@@ -72,7 +72,7 @@ typedef unsigned long old_sigset_t;
 #define SIGXFSZ 31
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define SIGRTMIN 32
-#define SIGRTMAX _NSIG
+#define SIGRTMAX _KERNEL__NSIG
 #define SA_ONSTACK 0x08000000
 #define SA_RESETHAND 0x80000000
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
diff --git a/libc/kernel/uapi/asm-x86/asm/signal.h b/libc/kernel/uapi/asm-x86/asm/signal.h
index bba6bc768..6f5b4354d 100644
--- a/libc/kernel/uapi/asm-x86/asm/signal.h
+++ b/libc/kernel/uapi/asm-x86/asm/signal.h
@@ -24,7 +24,7 @@
 #include <linux/time.h>
 #include <linux/compiler.h>
 struct siginfo;
-#define NSIG 32
+#define _KERNEL_NSIG 32
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 typedef unsigned long sigset_t;
 #endif
@@ -72,7 +72,7 @@ typedef unsigned long sigset_t;
 #define SIGUNUSED 31
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 #define SIGRTMIN 32
-#define SIGRTMAX _NSIG
+#define SIGRTMAX _KERNEL__NSIG
 #define SA_NOCLDSTOP 0x00000001u
 #define SA_NOCLDWAIT 0x00000002u
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
diff --git a/libc/kernel/uapi/asm-x86/asm/stat.h b/libc/kernel/uapi/asm-x86/asm/stat.h
index 09981062b..04c556909 100644
--- a/libc/kernel/uapi/asm-x86/asm/stat.h
+++ b/libc/kernel/uapi/asm-x86/asm/stat.h
@@ -102,7 +102,7 @@ struct stat {
  long __linux_unused[3];
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 };
-#define INIT_STRUCT_STAT_PADDING(st) do {   st.__pad0 = 0;   st.__unused[0] = 0;   st.__unused[1] = 0;   st.__unused[2] = 0;  } while (0)
+#define INIT_STRUCT_STAT_PADDING(st) do {   st.__pad0 = 0;   st.__linux_unused[0] = 0;   st.__linux_unused[1] = 0;   st.__linux_unused[2] = 0;  } while (0)
 #endif
 struct __old_kernel_stat {
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */