Replace __unused in kernel headers with __linux_unused to avoid
conflicts with __unused macro in sys/cdefs.h

Change-Id: Ice664397e0b7c7a90795012f30be5e43a9675525
diff --git a/libc/kernel/arch-arm/asm/ucontext.h b/libc/kernel/arch-arm/asm/ucontext.h
index 769f694..f54a7f1 100644
--- a/libc/kernel/arch-arm/asm/ucontext.h
+++ b/libc/kernel/arch-arm/asm/ucontext.h
@@ -27,7 +27,7 @@
  struct sigcontext uc_mcontext;
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
  sigset_t uc_sigmask;
- int __unused[32 - (sizeof (sigset_t) / sizeof (int))];
+ int __linux_unused[32 - (sizeof (sigset_t) / sizeof (int))];
  unsigned long uc_regspace[128] __attribute__((__aligned__(8)));
 };
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
diff --git a/libc/kernel/common/linux/sysctl.h b/libc/kernel/common/linux/sysctl.h
index 46e5e67..5769259 100644
--- a/libc/kernel/common/linux/sysctl.h
+++ b/libc/kernel/common/linux/sysctl.h
@@ -34,7 +34,7 @@
  size_t __user *oldlenp;
  void __user *newval;
  size_t newlen;
- unsigned long __unused[4];
+ unsigned long __linux_unused[4];
 /* WARNING: DO NOT EDIT, AUTO-GENERATED CODE - SEE TOP FOR INSTRUCTIONS */
 };
 enum
diff --git a/libc/kernel/tools/defaults.py b/libc/kernel/tools/defaults.py
index 7eeffb4..6c7efd6 100644
--- a/libc/kernel/tools/defaults.py
+++ b/libc/kernel/tools/defaults.py
@@ -51,6 +51,7 @@
 # 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
     }
 
 # this is the set of known static inline functions that we want to keep