From: Stephan Bergmann <sbergman@redhat.com>
Date: Fri, 24 Jun 2016 16:26:43 +0000 (+0000)
Subject: DeadStoresChecker: Don't warn about dead stores into volatile variables
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=07509dfa9efc989ea5d8cfc2e6d6c6332d583abd;p=clang

DeadStoresChecker: Don't warn about dead stores into volatile variables

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@273689 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/StaticAnalyzer/Checkers/DeadStoresChecker.cpp b/lib/StaticAnalyzer/Checkers/DeadStoresChecker.cpp
index f2a269a333..8ca2a24cff 100644
--- a/lib/StaticAnalyzer/Checkers/DeadStoresChecker.cpp
+++ b/lib/StaticAnalyzer/Checkers/DeadStoresChecker.cpp
@@ -278,6 +278,8 @@ public:
           RHS = RHS->IgnoreParenCasts();
 
           QualType T = VD->getType();
+          if (T.isVolatileQualified())
+            return;
           if (T->isPointerType() || T->isObjCObjectPointerType()) {
             if (RHS->isNullPointerConstant(Ctx, Expr::NPC_ValueDependentIsNull))
               return;
diff --git a/test/Analysis/dead-stores.c b/test/Analysis/dead-stores.c
index da8e8bdb70..cddb6c666a 100644
--- a/test/Analysis/dead-stores.c
+++ b/test/Analysis/dead-stores.c
@@ -569,3 +569,7 @@ void testBOComma() {
 
 }
 
+void testVolatile() {
+    volatile int v;
+    v = 0; // no warning
+}