r301522 - In the expression evaluator, visit the index of an ArraySubscriptExpr even if we can't evaluate the base, if the evaluation mode tells us to continue evaluation.

[Nick Lewycky via cfe-commits]

Author: nicholas
Date: Thu Apr 27 02:27:36 2017
New Revision: 301522

URL: http://llvm.org/viewvc/llvm-project?rev=301522&view=rev
Log:
In the expression evaluator, visit the index of an ArraySubscriptExpr even if we can't evaluate the base, if the evaluation mode tells us to continue evaluation.

Modified:
    cfe/trunk/lib/AST/ExprConstant.cpp
    cfe/trunk/test/Sema/integer-overflow.c

Modified: cfe/trunk/lib/AST/ExprConstant.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ExprConstant.cpp?rev=301522&r1=301521&r2=301522&view=diff
==============================================================================
--- cfe/trunk/lib/AST/ExprConstant.cpp (original)
+++ cfe/trunk/lib/AST/ExprConstant.cpp Thu Apr 27 02:27:36 2017
@@ -5246,14 +5246,19 @@ bool LValueExprEvaluator::VisitArraySubs
   if (E->getBase()->getType()->isVectorType())
     return Error(E);
 
-  if (!evaluatePointer(E->getBase(), Result))
-    return false;
+  bool Success = true;
+  if (!evaluatePointer(E->getBase(), Result)) {
+    if (!Info.noteFailure())
+      return false;
+    Success = false;
+  }
 
   APSInt Index;
   if (!EvaluateInteger(E->getIdx(), Index, Info))
     return false;
 
-  return HandleLValueArrayAdjustment(Info, E, Result, E->getType(), Index);
+  return Success &&
+         HandleLValueArrayAdjustment(Info, E, Result, E->getType(), Index);
 }
 
 bool LValueExprEvaluator::VisitUnaryDeref(const UnaryOperator *E) {

Modified: cfe/trunk/test/Sema/integer-overflow.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Sema/integer-overflow.c?rev=301522&r1=301521&r2=301522&view=diff
==============================================================================
--- cfe/trunk/test/Sema/integer-overflow.c (original)
+++ cfe/trunk/test/Sema/integer-overflow.c Thu Apr 27 02:27:36 2017
@@ -147,6 +147,10 @@ uint64_t check_integer_overflows(int i)
   uint64_t a[10];
   a[4608 * 1024 * 1024] = 1i;
 
+// expected-warning at +2 {{overflow in expression; result is 536870912 with type 'int'}}
+  uint64_t *b;
+  uint64_t b2 = b[4608 * 1024 * 1024] + 1;
+
 // expected-warning at +1 2{{overflow in expression; result is 536870912 with type 'int'}}
   (void)((i ? (4608 * 1024 * 1024) : (4608 * 1024 * 1024)) + 1);