From 2b03fbacf1ac0c06a84439baac90d418916a1778 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Bj=C3=B6rn=20Gustavsson?= Date: Fri, 26 Nov 2010 11:47:50 +0100 Subject: beam_utils: Fix check_liveness/3 for receive loops Sometimes the beam_bool pass wants to know whether an y register will be killed by the code that follows and will do (effectively): beam_utils:is_killed({y,Y}, Code, L) When asked to calculate the liveness for an y register, beam_utils:is_killed/3 will loop forever if the code includes a receive loop. Since this rarely occurs, fix the problem in the simplest and most conservative way. Reported-by: Christopher Williams --- lib/compiler/test/compilation_SUITE.erl | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) (limited to 'lib/compiler/test/compilation_SUITE.erl') diff --git a/lib/compiler/test/compilation_SUITE.erl b/lib/compiler/test/compilation_SUITE.erl index 7b6975f912..935e384d2d 100644 --- a/lib/compiler/test/compilation_SUITE.erl +++ b/lib/compiler/test/compilation_SUITE.erl @@ -46,7 +46,7 @@ all(suite) -> trycatch_4, opt_crash, otp_5404,otp_5436,otp_5481,otp_5553,otp_5632, otp_5714,otp_5872,otp_6121,otp_6121a,otp_6121b, - otp_7202,otp_7345,on_load,string_table,otp_8949_a + otp_7202,otp_7345,on_load,string_table,otp_8949_a,otp_8949_a ]. -define(comp(N), @@ -628,5 +628,23 @@ otp_8949_a() -> end end. +otp_8949_b(Config) when is_list(Config) -> + self() ! something, + ?line value = otp_8949_b([], false), + ?line {'EXIT',_} = (catch otp_8949_b([], true)), + ok. + +%% Would cause an endless loop in beam_utils. +otp_8949_b(A, B) -> + Var = id(value), + if + A == [], B == false -> + ok + end, + receive + something -> + id(Var) + end. + id(I) -> I. -- cgit v1.2.3