From 17f04c5043197968622539b98a2f73cc8f4ea6f0 Mon Sep 17 00:00:00 2001
From: Thomas Hume <aszarsha@gmail.com>
Date: Thu, 23 Feb 2017 00:58:08 +0100
Subject: [PATCH] Correct two overflows in PInt ctor

---
 src/dobjtype.cpp | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/dobjtype.cpp b/src/dobjtype.cpp
index 211c73e824..6684776da5 100644
--- a/src/dobjtype.cpp
+++ b/src/dobjtype.cpp
@@ -501,7 +501,7 @@ PInt::PInt(unsigned int size, bool unsign, bool compatible)
 	MemberOnly = (size < 4);
 	if (!unsign)
 	{
-		int maxval = (1 << ((8 * size) - 1)) - 1;
+		int maxval = (1u << ((8 * size) - 1)) - 1; // compute as unsigned to prevent overflow before -1
 		int minval = -maxval - 1;
 		Symbols.AddSymbol(new PSymbolConstNumeric(NAME_Min, this, minval));
 		Symbols.AddSymbol(new PSymbolConstNumeric(NAME_Max, this, maxval));
@@ -509,7 +509,7 @@ PInt::PInt(unsigned int size, bool unsign, bool compatible)
 	else
 	{
 		Symbols.AddSymbol(new PSymbolConstNumeric(NAME_Min, this, 0u));
-		Symbols.AddSymbol(new PSymbolConstNumeric(NAME_Max, this, (1u << (8 * size)) - 1));
+		Symbols.AddSymbol(new PSymbolConstNumeric(NAME_Max, this, (1u << ((8 * size) - 1))));
 	}
 	SetOps();
 }