Clean up more code

- Found some bugs in LLVM compiler-rt library
- The useless LIBC_STUBS package is now deleted
- Improve the overflow checking story even further
- Get chibicc tests working in MODE=dbg mode again
- The libc/isystem/ headers now have correctly named guards

third_party/lua/lmathlib.c

@@ -27,9 +27,9 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #define lmathlib_c
 #define LUA_LIB
+#include "libc/calls/calls.h"
 #include "libc/math.h"
 #include "libc/nt/struct/msg.h"
-#include "libc/time/time.h"
 #include "third_party/lua/lauxlib.h"
 #include "third_party/lua/lprefix.h"
 #include "third_party/lua/lua.h"

third_party/lua/ltablib.c

@@ -27,9 +27,9 @@
 ╚─────────────────────────────────────────────────────────────────────────────*/
 #define ltablib_c
 #define LUA_LIB
+#include "libc/calls/calls.h"
 #include "libc/calls/weirdtypes.h"
 #include "libc/str/str.h"
-#include "libc/time/time.h"
 #include "third_party/lua/lauxlib.h"
 #include "third_party/lua/lprefix.h"
 #include "third_party/lua/lua.h"

third_party/lua/lua.mk

@@ -194,7 +194,6 @@ THIRD_PARTY_LUA_UNIX_DIRECTDEPS =					\
 	LIBC_SOCK							\
 	LIBC_STDIO							\
 	LIBC_STR							\
-	LIBC_STUBS							\
 	LIBC_SYSV							\
 	LIBC_THREAD							\
 	LIBC_TIME							\

third_party/lua/lunix.c

@@ -52,7 +52,6 @@
 #include "libc/limits.h"
 #include "libc/log/log.h"
 #include "libc/macros.internal.h"
-#include "libc/mem/fmt.h"
 #include "libc/mem/mem.h"
 #include "libc/nt/runtime.h"
 #include "libc/nt/synchronization.h"