From cd21eb5b6afe384d044c44a8bb98f3c163532ecb Mon Sep 17 00:00:00 2001
From: Daniel Thayer <dnthayer@ncsa.illinois.edu>
Date: Wed, 5 Sep 2012 17:17:43 -0500
Subject: [PATCH] Fix the "-=" operator for intervals

Fixed a bug where "a -= b" (both operands are intervals) was not allowed in
bro scripts (although "a = a - b" is allowed).
---
 src/Expr.cc | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/Expr.cc b/src/Expr.cc
index e58e20f671..70aab46ab5 100644
--- a/src/Expr.cc
+++ b/src/Expr.cc
@@ -1516,6 +1516,8 @@ RemoveFromExpr::RemoveFromExpr(Expr* arg_op1, Expr* arg_op2)
 
 	if ( BothArithmetic(bt1, bt2) )
 		PromoteType(max_type(bt1, bt2), is_vector(op1) || is_vector(op2));
+	else if ( BothInterval(bt1, bt2) )
+		SetType(base_type(bt1));
 	else
 		ExprError("requires two arithmetic operands");
 	}