Index: src/output.d
==================================================================
--- src/output.d
+++ src/output.d
@@ -52,11 +52,11 @@
 	bool   flushed;
 
 	string s_log;
 	long[] s_score_log;
 
-	void flush()
+	void flush() nothrow
 	{
 		if(flushed)
 			return;
 
 		Tuple!(long, int, immutable(char)*) cand;
@@ -79,9 +79,9 @@
 
 	void setup_sigint_handling()
 	{
 		assert(g_output is null);
 		g_output = this;
-		extern(C) static void catch_sigint(int) { g_output.flush(); application_exit(); }
+		extern(C) nothrow @system static void catch_sigint(int) { g_output.flush(); application_exit(); }
 		core.stdc.signal.signal(SIGINT, &catch_sigint);
 	}
 }

Index: src/solver.d
==================================================================
--- src/solver.d
+++ src/solver.d
@@ -85,11 +85,11 @@
 {
 	alias Tuple!(T,int) t;
 
 	t[] cur, next;
 
-	void push(T v, int p) { (cur.empty ? cur : next) ~= tuple(v,p); }
+	void push(T v, int p) { if(cur.empty) cur ~= tuple(v,p); else next ~= tuple(v,p); }
 	bool empty() { return cur.empty; }
 	t pop() {
 		t v = cur[0]; cur = cur[1..$];
 		if(cur.empty) { cur = next; next = null; }
 		return v;

Index: src/util.d
==================================================================
--- src/util.d
+++ src/util.d
@@ -20,11 +20,11 @@
 		if(e == v)
 			++cnt;
 	return cnt;
 }
 
-void application_exit()
+void application_exit() nothrow
 {
 	std.c.stdlib.exit(0);
 }
 
 template DeriveCreate()