id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc	os	architecture	failure	difficulty	testcase	blockedby	blocking	related
3591	A working program reports <<loop>> when compiled with -O	blamario	igloo	"If the attached module Trampoline.hs is compiled with no optimizations it works:

{{{
$ ghc --make Trampoline.hs   
[1 of 1] Compiling Main             ( Trampoline.hs, Trampoline.o )
Linking Trampoline ...
$ ./Trampoline 
...
((5,2),(1,2,6))
$ 
}}}

With optimizations on, it hangs:

{{{
$ ghc --make Trampoline.hs -O
[1 of 1] Compiling Main             ( Trampoline.hs, Trampoline.o )
Linking Trampoline ...
$ ./Trampoline 
bounce start
bounce end
liftOut
inject suspend
Trampoline: <<loop>>
}}}

That doesn't seem right. Oh, GHCi runs it with no problem as well.

"	merge	closed	normal	6.12.1	Compiler	6.10.4	fixed			Linux	x86_64 (amd64)	None/Unknown	Unknown	simplCore/should_run/T3591