r273689 - DeadStoresChecker: Don't warn about dead stores into volatile variables

[Stephan Bergmann via cfe-commits]

Author: sberg
Date: Fri Jun 24 11:26:43 2016
New Revision: 273689

URL: http://llvm.org/viewvc/llvm-project?rev=273689&view=rev
Log:
DeadStoresChecker: Don't warn about dead stores into volatile variables

Modified:
    cfe/trunk/lib/StaticAnalyzer/Checkers/DeadStoresChecker.cpp
    cfe/trunk/test/Analysis/dead-stores.c

Modified: cfe/trunk/lib/StaticAnalyzer/Checkers/DeadStoresChecker.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/StaticAnalyzer/Checkers/DeadStoresChecker.cpp?rev=273689&r1=273688&r2=273689&view=diff
==============================================================================
--- cfe/trunk/lib/StaticAnalyzer/Checkers/DeadStoresChecker.cpp (original)
+++ cfe/trunk/lib/StaticAnalyzer/Checkers/DeadStoresChecker.cpp Fri Jun 24 11:26:43 2016
@@ -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;

Modified: cfe/trunk/test/Analysis/dead-stores.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Analysis/dead-stores.c?rev=273689&r1=273688&r2=273689&view=diff
==============================================================================
--- cfe/trunk/test/Analysis/dead-stores.c (original)
+++ cfe/trunk/test/Analysis/dead-stores.c Fri Jun 24 11:26:43 2016
@@ -569,3 +569,7 @@ void testBOComma() {
 
 }
 
+void testVolatile() {
+    volatile int v;
+    v = 0; // no warning
+}