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

libc/mem/fmt.h

@@ -1,12 +0,0 @@
-#ifndef COSMOPOLITAN_LIBC_MEM_FMT_H_
-#define COSMOPOLITAN_LIBC_MEM_FMT_H_
-#if !(__ASSEMBLER__ + __LINKER__ + 0)
-COSMOPOLITAN_C_START_
-
-int asprintf(char **, const char *, ...) printfesque(2)
-    paramsnonnull((1, 2)) libcesque;
-int vasprintf(char **, const char *, va_list) paramsnonnull() libcesque;
-
-COSMOPOLITAN_C_END_
-#endif /* !(__ASSEMBLER__ + __LINKER__ + 0) */
-#endif /* COSMOPOLITAN_LIBC_MEM_FMT_H_ */

libc/mem/mem.mk

@@ -17,14 +17,13 @@ LIBC_MEM_A_CHECKS =				\
 
 LIBC_MEM_A_DIRECTDEPS =				\
 	LIBC_CALLS				\
-	LIBC_SYSV_CALLS				\
 	LIBC_FMT				\
 	LIBC_INTRIN				\
 	LIBC_NEXGEN32E				\
 	LIBC_RUNTIME				\
 	LIBC_STR				\
-	LIBC_STUBS				\
 	LIBC_SYSV				\
+	LIBC_SYSV_CALLS				\
 	THIRD_PARTY_DLMALLOC
 
 LIBC_MEM_A_DEPS :=				\