Fix warnings

This change fixes Cosmopolitan so it has fewer opinions about compiler
warnings. The whole repository had to be cleaned up to be buildable in
-Werror -Wall mode. This lets us benefit from things like strict const
checking. Some actual bugs might have been caught too.

libc/log/oncrash_arm64.c

@@ -28,6 +28,7 @@
 #include "libc/calls/syscall-sysv.internal.h"
 #include "libc/calls/ucontext.h"
 #include "libc/errno.h"
+#include "libc/intrin/describeflags.internal.h"
 #include "libc/intrin/kprintf.h"
 #include "libc/log/internal.h"
 #include "libc/log/log.h"
@@ -132,9 +133,10 @@ static bool AppendFileLine(struct Buffer *b, const char *addr2line,
     sys_close(pfd[0]);
     sys_dup2(pfd[1], 1, 0);
     sys_close(2);
-    __sys_execve(addr2line,
-                 (char *const[]){addr2line, "-pifCe", debugbin, buf, 0},
-                 (char *const[]){0});
+    __sys_execve(
+        addr2line,
+        (char *const[]){(char *)addr2line, "-pifCe", (char *)debugbin, buf, 0},
+        (char *const[]){0});
     _Exit(127);
   }
   sys_close(pfd[1]);
@@ -202,7 +204,7 @@ relegated void __oncrash_arm64(int sig, struct siginfo *si, void *arg) {
         (ctx->uc_mcontext.sp & (GetStackSize() - 1)) <= getauxval(AT_PAGESZ)) {
       kind = "Stack Overflow";
     } else {
-      kind = GetSiCodeName(sig, si->si_code);
+      kind = DescribeSiCode(sig, si->si_code);
     }
     Append(b,
            "%serror%s: Uncaught %G (%s) on %s pid %d tid %d\n"
@@ -216,7 +218,6 @@ relegated void __oncrash_arm64(int sig, struct siginfo *si, void *arg) {
            names.release);
     if (ctx) {
       long pc;
-      char line[256];
       char *mem = 0;
       size_t memsz = 0;
       int addend, symbol;