Make terminal ui binaries work well everywhere

Here's some screenshots of an emulator tui program that was compiled on
Linux, then scp'd it to Windows, Mac, and FreeBSD.

https://justine.storage.googleapis.com/blinkenlights-cmdexe.png
https://justine.storage.googleapis.com/blinkenlights-imac.png
https://justine.storage.googleapis.com/blinkenlights-freebsd.png
https://justine.storage.googleapis.com/blinkenlights-lisp.png

How is this even possible that we have a nontrivial ui binary that just
works on Mac, Windows, Linux, and BSD? Surely a first ever achievement.

Fixed many bugs. Bootstrapped John McCarthy's metacircular evaluator on
bare metal in half the size of Altair BASIC (about 2.5kb) and ran it in
emulator for fun and profit.

libc/runtime/executive.S

@@ -57,42 +57,14 @@ _executive:
 	ud2
 
 #ifdef __PG__
-/	Enables plaintext function tracing if --ftrace flag passed.
-/
-/	The --ftrace CLI arg is removed before main() is called. This
-/	code is intended for diagnostic purposes and assumes binaries
-/	are trustworthy and stack isn't corrupted. Logging plain text
-/	allows program structure to easily be visualized and hotspots
-/	identified w/ sed | sort | uniq -c | sort. A compressed trace
-/	can be made by appending --ftrace 2>&1 | gzip -4 >trace.gz to
-/	the CLI arguments. Have fun.
-/
-/	@see	libc/runtime/ftrace.greg.c
-/	@see	libc/crt/crt.S
 	.init.start 800,_init_ftrace
 	push	%rdi
 	push	%rsi
-	xor	%edx,%edx
-	loadstr	"--ftrace",di
-	xor	%ecx,%ecx
-0:	inc	%ecx
-	mov	(%r13,%rcx,8),%rsi
-	test	%edx,%edx
-	jz	1f
-	mov	%rsi,-8(%r13,%rcx,8)
-1:	test	%rsi,%rsi
-	jz	2f
-	test	%edx,%edx
-	jnz	0b
-	call	tinystrcmp
-	test	%eax,%eax
-	setz	%dl
-	jmp	0b
-2:	sub	%rdx,%r12
-	test	%edx,%edx
-	jz	2f
+	mov	%r12d,%edi
+	mov	%r13,%rsi
 	call	ftrace_init
-2:	pop	%rsi
+	mov	%eax,%r12d
+	pop	%rsi
 	pop	%rdi
 	.init.end 800,_init_ftrace
-#endif /* -pg */
+#endif