branch-bug.pn

say = (msg): msg string print, "\n" print.
say2 = (label, value): label print, ":  " print, value print, "\n" print.


wrongness = (n):
	if (n == 0):
		say("In n == 0 branch")
		1
		.
	else:
		say("In n != 0 branch")
		.
	.

say2("wrongness(0)", wrongness(0))


fib = (n):
	say("in fib")
	say(n)
	if (n < 2):
		say("n < 2")
		# I can't get this to work no matter what:
		# return(1)
		# Nor any of this:
		# result = 1
		# say2("result", result)
		# say2("1", 1)
		# This isn't working either:
		# They all fail when trying to print the "1", lookup failed on 'print'.
		1
		.
	else:
		say("n >= 2")
		x = self fib(n-2)
		say("got x")
		say2("x", x)
		y = self fib(n-1)
		say2("y", y)
		say2("x + y + 1", x + y + 1)
		return(x + y + 1)
		# Doesn't work, returns nil.
		# return self fib(n-2) + self fib(n-1) + 1
		.
	.

say2("fib(10)", fib(10))

# This fails, even in the bytecode interpreter, and the reason seems to be bad
# codegen for "else".  Rather than ending the "if" branch with a jump past the
# "else" branch, the compiler starts the "else" branch with a "testjmp".
# Apparently it thinks it arrived here from the "if"'s test (a "notjmp"), but
# of course the "if" branch can clobber the value.