From: Matthieu Volat <mazhe@alkumuna.eu>
Date: Thu, 12 Jan 2017 13:13:47 +0000 (+0100)
Subject: Fix an undefined C behavior.
X-Git-Tag: v3_15~557
X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/366e4448e231ced837b609f05f73f2aabe5e0750?hp=30d088f255192e7dde37bf961570af5b1c1db153

Fix an undefined C behavior.

This will fix the minus operation on certain OS/compilers.
---

diff --git a/src/mc/DwarfExpression.cpp b/src/mc/DwarfExpression.cpp
index 6cdba68ae1..03298eb6ba 100644
--- a/src/mc/DwarfExpression.cpp
+++ b/src/mc/DwarfExpression.cpp
@@ -225,9 +225,12 @@ void execute(
       stack.top() = - (intptr_t) stack.top();
       break;
 
-    case DW_OP_minus:
-      stack.push(stack.pop() - stack.pop());
+    case DW_OP_minus: {
+      intptr_t first = stack.pop();
+      intptr_t second = stack.pop();
+      stack.push(second - first);
       break;
+    }
 
     case DW_OP_and:
       stack.push(stack.pop() & stack.pop());