Get codebase completely working with LLVM

You can now build Cosmopolitan with Clang:

    make -j8 MODE=llvm
    o/llvm/examples/hello.com

The assembler and linker code is now friendly to LLVM too.
So it's not needed to configure Clang to use binutils under
the hood. If you love LLVM then you can now use pure LLVM.

tool/decode/elf.c

@@ -26,6 +26,7 @@
 #include "libc/fmt/conv.h"
 #include "libc/log/check.h"
 #include "libc/log/log.h"
+#include "libc/macros.h"
 #include "libc/stdio/stdio.h"
 #include "libc/str/str.h"
 #include "libc/sysv/consts/map.h"
@@ -282,7 +283,7 @@ static void printelfrelocations(void) {
                    GetElfSectionHeaderAddress(elf, st->st_size, shdr->sh_info)
                        ->sh_name),
                rela->r_offset, symbolname, rela->r_addend >= 0 ? '+' : '-',
-               abs(rela->r_addend));
+               ABS(rela->r_addend));
         printf("%s_%zu_%zu:\n", ".Lrela", i, j);
         show(".quad", format(b1, "%#lx", rela->r_offset), "rela->r_offset");
         show(".long",

tool/decode/lib/pollnames.S

@@ -47,8 +47,8 @@ kPollNamesRo:
 	.endobj	kPollNamesRo,globl,hidden
 	.previous
 
-/	Mapping of poll() flags to their string names.
-/	@see	RecreateFlags()
+//	Mapping of poll() flags to their string names.
+//	@see	RecreateFlags()
 	.initbss 301,_init_kPollNames
 kPollNames:
 	.rept	.Lrows
@@ -62,10 +62,11 @@ kPollNames:
 	.init.start 301,_init_kPollNames
 	pushpop	.Lrows,%rcx		# relocate RO→BSS b/c -fPIE crap
 0:	lodsl
-	mov	(%rbx,%rax),%rax	# read what systemfive.S decoded
+	.weak	_base
+	mov	_base(%rax),%rax	# read what systemfive.S decoded
 	stosq
 	lodsl
-	add	%rbx,%rax		# %rbx is image base (cosmo abi)
+	add	$_base,%rax
 	stosq
 	.loop	0b
 	add	$16,%rdi