Fix bugs in cosmocc toolchain

This change integrates e58abc1110b335a3341e8ad5821ad8e3880d9bb2 from
https://github.com/ahgamut/musl-cross-make/ which fixes the issues we
were having with our C language extension for symbolic constants. This
change also performs some code cleanup and bug fixes to getaddrinfo().
It's now possible to compile projects like ncurses, readline and python
without needing to patch anything upstream, except maybe a line or two.
Pretty soon it should be possible to build a Linux distro on Cosmo.

libc/intrin/exit.c

@@ -88,7 +88,7 @@ wontreturn void _Exit(int exitcode) {
       "lidt\t(%rsp)");
   for (;;) asm("ud2");
 #else
-  unreachable;
+  __builtin_unreachable();
 #endif
 }
 

libc/intrin/exit1.greg.c

@@ -67,11 +67,11 @@ privileged wontreturn void _Exit1(int rc) {
                    : /* no outputs */
                    : "a"(__NR_exit_group), "D"(rc)
                    : "rcx", "r11", "memory");
-      unreachable;
+      __builtin_unreachable();
     }
   } else if (IsWindows()) {
     __imp_ExitThread(rc);
-    unreachable;
+    __builtin_unreachable();
   }
   notpossible;
 #elif defined(__aarch64__)

libc/intrin/g_fds.c

@@ -35,7 +35,7 @@ STATIC_YOINK("_init_g_fds");
 #endif
 
 struct Fds g_fds;
-static struct Fd g_fds_static[8];
+static struct Fd g_fds_static[OPEN_MAX];
 
 static textwindows dontinline void SetupWinStd(struct Fds *fds, int i, int x) {
   int64_t h;
@@ -46,7 +46,7 @@ static textwindows dontinline void SetupWinStd(struct Fds *fds, int i, int x) {
   atomic_store_explicit(&fds->f, i + 1, memory_order_relaxed);
 }
 
-textstartup void InitializeFileDescriptors(void) {
+textstartup void __init_fds(void) {
   struct Fds *fds;
   __fds_lock_obj._type = PTHREAD_MUTEX_RECURSIVE;
   fds = VEIL("r", &g_fds);
@@ -59,7 +59,7 @@ textstartup void InitializeFileDescriptors(void) {
                          kMemtrackFdsStart + kMemtrackFdsSize);
   } else {
     fds->p = g_fds_static;
-    fds->e = g_fds_static + ARRAYLEN(g_fds_static);
+    fds->e = g_fds_static + OPEN_MAX;
   }
   if (IsMetal()) {
     extern const char vga_console[];

libc/intrin/g_fds_init.S

@@ -21,7 +21,7 @@
 	.init.start 305,_init_g_fds
 	push	%rdi
 	push	%rsi
-	call	InitializeFileDescriptors
+	call	__init_fds
 	pop	%rsi
 	pop	%rdi
 	.init.end 305,_init_g_fds

libc/intrin/kprintf.greg.c

@@ -267,6 +267,7 @@ privileged static size_t kformat(char *b, size_t n, const char *fmt,
   p = b;
   f = fmt;
   e = p + n;  // assume if n was negative e < p will be the case
+  tib = __tls_enabled ? __get_tls_privileged() : 0;
   for (;;) {
     for (;;) {
       if (!(c = *f++) || c == '%') break;
@@ -377,7 +378,6 @@ privileged static size_t kformat(char *b, size_t n, const char *fmt,
           goto FormatUnsigned;
 
         case 'P':
-          tib = __tls_enabled ? __get_tls_privileged() : 0;
           if (!(tib && (tib->tib_flags & TIB_FLAG_VFORKED))) {
             if (tib) {
               x = atomic_load_explicit(&tib->tib_tid, memory_order_relaxed);
@@ -524,7 +524,7 @@ privileged static size_t kformat(char *b, size_t n, const char *fmt,
         case 'm': {
           int unixerr;
           uint32_t winerr;
-          unixerr = errno;
+          unixerr = tib ? tib->tib_errno : __errno;
           winerr = 0;
           if (IsWindows()) {
             if (type == 1 && _weaken(__imp_WSAGetLastError)) {

libc/intrin/leaky.S

@@ -19,7 +19,7 @@
 #include "libc/macros.internal.h"
 
 //	Decentralized section for leaky functions.
-	.section .piro.relo.sort.leaky.1,"aw",@nobits
+	.section .piro.relo.sort.leaky.1,"aw",@progbits
 	.type	_leaky_start,@object
 	.type	_leaky_end,@object
 	.globl	_leaky_start,_leaky_end
@@ -32,7 +32,7 @@ _leaky_start:
 	...
 	decentralized content
 	...
-	*/.section .piro.relo.sort.leaky.3,"aw",@nobits
+	*/.section .piro.relo.sort.leaky.3,"aw",@progbits
 _leaky_end:
 	.quad	0
 	.overrun

libc/intrin/winerr.greg.c

@@ -24,6 +24,7 @@
 #include "libc/nt/runtime.h"
 #include "libc/sock/internal.h"
 #include "libc/sysv/errfuns.h"
+#include "libc/thread/tls2.h"
 
 /**
  * Return path for failed Win32 API calls.
@@ -38,6 +39,10 @@ privileged int64_t __winerr(void) {
   } else {
     e = ENOSYS;
   }
-  errno = e;
+  if (__tls_enabled) {
+    __get_tls_privileged()->tib_errno = e;
+  } else {
+    __errno = e;
+  }
   return -1;
 }