Add chibicc

This program popped up on Hacker News recently. It's the only modern
compiler I've ever seen that doesn't have dependencies and is easily
modified. So I added all of the missing GNU extensions I like to use
which means it might be possible soon to build on non-Linux and have
third party not vendor gcc binaries.

examples/cp.c

@@ -42,7 +42,7 @@ FLAGS\n\
 int flags;
 bool force;
 
-noreturn void PrintUsage(int rc, FILE *f) {
+wontreturn void PrintUsage(int rc, FILE *f) {
   fprintf(f, "%s%s%s", "Usage: ", program_invocation_name, USAGE);
   exit(rc);
 }

examples/examples.mk

@@ -72,7 +72,7 @@ EXAMPLES_DIRECTDEPS =						\
 	LIBC_ZIPOS						\
 	THIRD_PARTY_COMPILER_RT					\
 	THIRD_PARTY_DLMALLOC					\
-	THIRD_PARTY_DTOA					\
+	THIRD_PARTY_GDTOA					\
 	THIRD_PARTY_GETOPT					\
 	THIRD_PARTY_MUSL					\
 	THIRD_PARTY_STB						\

examples/invtsc.c

@@ -18,7 +18,7 @@
 #include "libc/sysv/consts/sig.h"
 #include "libc/time/time.h"
 #include "libc/x/x.h"
-#include "third_party/dtoa/dtoa.h"
+#include "third_party/gdtoa/gdtoa.h"
 
 /**
  * @fileoverview Measure CPU clock mystery constants.
@@ -52,15 +52,18 @@ long double GetSample(void) {
 
 void MeasureNanosecondsPerAlwaysRunningTimerCycle(void) {
   int i;
-  long double avg, samp;
+  long double avg, samp, elapsed;
   start_ = now();
   for (i = 1, avg = 1.0L; !isdone_; ++i) {
     samp = GetSample();
     avg += (samp - avg) / i;
     dsleep(kInterval);
-    printf("1c = %sns (last=%sns spent=%ss)\n", g_fmt(dtoabuf_[0], (double)avg),
-           g_fmt(dtoabuf_[1], (double)samp),
-           g_fmt(dtoabuf_[2], (double)(now() - start_)));
+    elapsed = now() - start_;
+    g_xfmt_p(dtoabuf_[0], &avg, 15, 32, 0);
+    g_xfmt_p(dtoabuf_[1], &samp, 15, 32, 0);
+    g_xfmt_p(dtoabuf_[2], &elapsed, 15, 32, 0);
+    printf("1c = %sns (last=%sns spent=%ss)\n", dtoabuf_[0], dtoabuf_[1],
+           dtoabuf_[2]);
   }
 }
 

examples/nesemu1.cc

@@ -1774,7 +1774,7 @@ Press enter to continue without sound: ",
   for (;;) CPU::Op();
 }
 
-noreturn void PrintUsage(int rc, FILE* f) {
+wontreturn void PrintUsage(int rc, FILE* f) {
   fprintf(f, "%s%s%s", "Usage: ", program_invocation_name, USAGE);
   exit(rc);
 }

examples/now.c

@@ -1,34 +0,0 @@
-#if 0
-/*─────────────────────────────────────────────────────────────────╗
-│ To the extent possible under law, Justine Tunney has waived      │
-│ all copyright and related or neighboring rights to this file,    │
-│ as it is written in the following disclaimers:                   │
-│   • http://unlicense.org/                                        │
-│   • http://creativecommons.org/publicdomain/zero/1.0/            │
-╚─────────────────────────────────────────────────────────────────*/
-#endif
-#include "libc/bits/bits.h"
-#include "libc/bits/safemacros.internal.h"
-#include "libc/calls/calls.h"
-#include "libc/dce.h"
-#include "libc/stdio/stdio.h"
-#include "libc/sysv/consts/clock.h"
-#include "libc/time/time.h"
-#include "third_party/dtoa/dtoa.h"
-
-char dtoabuf_[3][32];
-
-static long double avg;
-
-int main(int argc, char *argv[]) {
-  long double t2, t1 = nowl();
-  dsleep(0.3);
-  for (;;) {
-    t2 = nowl();
-    printf("%s %s avg=%s\n", g_fmt(dtoabuf_[0], t2),
-           g_fmt(dtoabuf_[1], t2 - t1), g_fmt(dtoabuf_[2], avg));
-    t1 = t2;
-    dsleep(0.3);
-  }
-  return 0;
-}

examples/unbourne.c

@@ -141,7 +141,7 @@
 #include "libc/sysv/consts/rlim.h"
 #include "libc/sysv/consts/sig.h"
 #include "libc/sysv/consts/w.h"
-#include "third_party/dtoa/dtoa.h"
+#include "third_party/gdtoa/gdtoa.h"
 #include "third_party/musl/passwd.h"
 
 #undef CEOF
@@ -1602,7 +1602,7 @@ static inline void sigclearmask(void) {
  * just do a longjmp to the exception handler.  The type of exception is
  * stored in the global variable "exception".
  */
-noreturn static void exraise(int e) {
+wontreturn static void exraise(int e) {
   if (vforked) _exit(exitstatus);
   INTOFF;
   exception = e;
@@ -1617,7 +1617,7 @@ noreturn static void exraise(int e) {
  * are held using the INTOFF macro.  (The test for iflag is just
  * defensive programming.)
  */
-noreturn static void onint(void) {
+wontreturn static void onint(void) {
   intpending = 0;
   sigclearmask();
   if (!(rootshell && iflag)) {
@@ -1896,20 +1896,20 @@ printfesque(1) static void sh_warnx(const char *fmt, ...) {
  * is not NULL then error prints an error message using printf style
  * formatting.  It then raises the error exception.
  */
-noreturn static void exverror(int cond, const char *msg, va_list ap) {
+wontreturn static void exverror(int cond, const char *msg, va_list ap) {
   exvwarning(msg, ap);
   flushall();
   exraise(cond);
 }
 
-noreturn static void exerror(int cond, const char *msg, ...) {
+wontreturn static void exerror(int cond, const char *msg, ...) {
   va_list ap;
   va_start(ap, msg);
   exverror(cond, msg, ap);
   va_end(ap);
 }
 
-noreturn static void sh_error(const char *msg, ...) {
+wontreturn static void sh_error(const char *msg, ...) {
   va_list ap;
   exitstatus = 2;
   va_start(ap, msg);
@@ -1917,16 +1917,16 @@ noreturn static void sh_error(const char *msg, ...) {
   va_end(ap);
 }
 
-noreturn static void badnum(const char *s) {
+wontreturn static void badnum(const char *s) {
   sh_error(illnum, s);
 }
 
-noreturn static void synerror(const char *msg) {
+wontreturn static void synerror(const char *msg) {
   errlinno = plinno;
   sh_error("Syntax error: %s", msg);
 }
 
-noreturn static void yyerror(const char *s) {
+wontreturn static void yyerror(const char *s) {
   sh_error("arithmetic expression: %s: \"%s\"", s, arith_startbuf);
 }
 
@@ -1935,7 +1935,7 @@ noreturn static void yyerror(const char *s) {
  * argument is the token that is expected, or -1 if more than one type
  * of token can occur at this point.
  */
-noreturn static void synexpect(int token) {
+wontreturn static void synexpect(int token) {
   char msg[64];
   if (token >= 0) {
     fmtstr(msg, 64, "%s unexpected (expecting %s)", tokname[lasttoken], tokname[token]);
@@ -1945,7 +1945,7 @@ noreturn static void synexpect(int token) {
   synerror(msg);
 }
 
-noreturn static void varunset(const char *end, const char *var_, const char *umsg, int varflags) {
+wontreturn static void varunset(const char *end, const char *var_, const char *umsg, int varflags) {
   const char *msg;
   const char *tail;
   tail = nullstr;
@@ -2096,7 +2096,7 @@ static char *nodesavestr(s) char *s;
   return rtn;
 }
 
-noreturn static void shellexec(char **, const char *, int);
+wontreturn static void shellexec(char **, const char *, int);
 static char **listvars(int, int, char ***);
 static char *argstr(char *p, int flag);
 static char *conv_escape(char *, int *);
@@ -3175,7 +3175,7 @@ out:
   return exitstatus;
 }
 
-noreturn static void evaltreenr(union node *n, int flags) {
+wontreturn static void evaltreenr(union node *n, int flags) {
   evaltree(n, flags);
   abort();
 }
@@ -3876,7 +3876,7 @@ static int eprintlist(struct output *out, struct strlist *sp, int sep) {
  * Exec a program.  Never returns.  If you change this routine, you may
  * have to change the find_command routine as well.
  */
-noreturn static void shellexec(char **argv, const char *path, int idx) {
+wontreturn static void shellexec(char **argv, const char *path, int idx) {
   char *cmdname;
   int e;
   char **envp;
@@ -9316,7 +9316,7 @@ static void setinteractive(int on) {
 /*
  * Called to exit the shell.
  */
-noreturn static void exitshell(void) {
+wontreturn static void exitshell(void) {
   struct jmploc loc;
   char *p;
   savestatus = exitstatus;