[Sema] CheckTautologicalComparisonWithZero(): always complain about enums

Hopefully fixes test-clang-msc-x64-on-i686-linux-RA build.

The underlying problem is that the enum is signed there.
Yet still, it is invalid for it to contain negative values,
so the comparison is always tautological in this case.

No differential, but related to https://reviews.llvm.org/D37629

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@313747 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Sema/SemaChecking.cpp b/lib/Sema/SemaChecking.cpp
index 87634ad57e51490147f6974bf20576b03bafc09d..9ff8f6347e7edb01f13625355002bd557c4c2a02 100644 (file)
--- a/lib/Sema/SemaChecking.cpp
+++ b/lib/Sema/SemaChecking.cpp
@@ -8592,22 +8592,26 @@ bool CheckTautologicalComparisonWithZero(Sema &S, BinaryOperator *E) {
 
   bool Match = true;
 
-  if (Op == BO_LT && isNonBooleanUnsignedValue(LHS) && IsZero(S, RHS)) {
+  if (Op == BO_LT && IsZero(S, RHS) &&
+      (isNonBooleanUnsignedValue(LHS) || HasEnumType(LHS))) {
     S.Diag(E->getOperatorLoc(),
            HasEnumType(LHS) ? diag::warn_lunsigned_enum_always_true_comparison
                             : diag::warn_lunsigned_always_true_comparison)
         << "< 0" << false << LHS->getSourceRange() << RHS->getSourceRange();
-  } else if (Op == BO_GE && isNonBooleanUnsignedValue(LHS) && IsZero(S, RHS)) {
+  } else if (Op == BO_GE && IsZero(S, RHS) &&
+             (isNonBooleanUnsignedValue(LHS) || HasEnumType(LHS))) {
     S.Diag(E->getOperatorLoc(),
            HasEnumType(LHS) ? diag::warn_lunsigned_enum_always_true_comparison
                             : diag::warn_lunsigned_always_true_comparison)
         << ">= 0" << true << LHS->getSourceRange() << RHS->getSourceRange();
-  } else if (Op == BO_GT && isNonBooleanUnsignedValue(RHS) && IsZero(S, LHS)) {
+  } else if (Op == BO_GT && IsZero(S, LHS) &&
+             (isNonBooleanUnsignedValue(RHS) || HasEnumType(RHS))) {
     S.Diag(E->getOperatorLoc(),
            HasEnumType(RHS) ? diag::warn_runsigned_enum_always_true_comparison
                             : diag::warn_runsigned_always_true_comparison)
         << "0 >" << false << LHS->getSourceRange() << RHS->getSourceRange();
-  } else if (Op == BO_LE && isNonBooleanUnsignedValue(RHS) && IsZero(S, LHS)) {
+  } else if (Op == BO_LE && IsZero(S, LHS) &&
+             (isNonBooleanUnsignedValue(RHS) || HasEnumType(RHS))) {
     S.Diag(E->getOperatorLoc(),
            HasEnumType(RHS) ? diag::warn_runsigned_enum_always_true_comparison
                             : diag::warn_runsigned_always_true_comparison)