From: Clifford Wolf <clifford@clifford.at>
Date: Fri, 8 Aug 2014 12:55:11 +0000 (+0200)
Subject: Another fsm_extract bugfix
X-Git-Tag: yosys-0.4~288
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=58ac605470aed3b2a537b4f99ac17a199f8b5233;p=yosys.git

Another fsm_extract bugfix
---

diff --git a/passes/fsm/fsm_extract.cc b/passes/fsm/fsm_extract.cc
index 7533b4a33..ebe3073de 100644
--- a/passes/fsm/fsm_extract.cc
+++ b/passes/fsm/fsm_extract.cc
@@ -231,6 +231,10 @@ static void extract_fsm(RTLIL::Wire *wire)
 		log("  fsm extraction failed: state selection tree is not closed.\n");
 		return;
 	}
+	if (SIZE(states) <= 1) {
+		log("  fsm extraction failed: at least two states are required.\n");
+		return;
+	}
 
 	// find control outputs
 	// (add the state signals to the list of control outputs. if everything goes right, this signals