r198913 - Make the tautological out of range warning use Sema::DiagRuntimeBehavior so that

[Richard Trieu]

Author: rtrieu
Date: Thu Jan  9 22:38:09 2014
New Revision: 198913

URL: http://llvm.org/viewvc/llvm-project?rev=198913&view=rev
Log:
Make the tautological out of range warning use Sema::DiagRuntimeBehavior so that
the warning will not trigger on code protected by compile time checks.

Added:
    cfe/trunk/test/SemaCXX/warn-tautological-compare.cpp
Modified:
    cfe/trunk/lib/Sema/SemaChecking.cpp

Modified: cfe/trunk/lib/Sema/SemaChecking.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaChecking.cpp?rev=198913&r1=198912&r2=198913&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaChecking.cpp (original)
+++ cfe/trunk/lib/Sema/SemaChecking.cpp Thu Jan  9 22:38:09 2014
@@ -4970,9 +4970,11 @@ static void DiagnoseOutOfRangeComparison
   else
     OS << Value;
 
-  S.Diag(E->getOperatorLoc(), diag::warn_out_of_range_compare)
-      << OS.str() << OtherT << IsTrue
-      << E->getLHS()->getSourceRange() << E->getRHS()->getSourceRange();
+  S.DiagRuntimeBehavior(E->getOperatorLoc(), E,
+                        S.PDiag(diag::warn_out_of_range_compare)
+                          << OS.str() << OtherT << IsTrue
+                          << E->getLHS()->getSourceRange()
+                          << E->getRHS()->getSourceRange());
 }
 
 /// Analyze the operands of the given comparison.  Implements the

Added: cfe/trunk/test/SemaCXX/warn-tautological-compare.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/warn-tautological-compare.cpp?rev=198913&view=auto
==============================================================================
--- cfe/trunk/test/SemaCXX/warn-tautological-compare.cpp (added)
+++ cfe/trunk/test/SemaCXX/warn-tautological-compare.cpp Thu Jan  9 22:38:09 2014
@@ -0,0 +1,27 @@
+// Force x86-64 because some of our heuristics are actually based
+// on integer sizes.
+
+// RUN: %clang_cc1 -triple x86_64-apple-darwin -fsyntax-only -verify -std=c++11 %s
+
+namespace RuntimeBehavior {
+  // Avoid emitting tautological compare warnings when the code already has
+  // compile time checks on variable sizes.
+
+  const int kintmax = 2147483647;
+  void test0(short x) {
+    if (sizeof(x) < sizeof(int) || x < kintmax) {}
+
+    if (x < kintmax) {}
+    // expected-warning at -1{{comparison of constant 2147483647 with expression of type 'short' is always true}}
+  }
+
+  void test1(short x) {
+    if (x < kintmax) {}
+    // expected-warning at -1{{comparison of constant 2147483647 with expression of type 'short' is always true}}
+
+    if (sizeof(x) < sizeof(int))
+      return;
+
+    if (x < kintmax) {}
+  }
+}