refine the "use of unary operator that may be intended as compound assignment (+=)"

warning to only trigger when there is whitespace or something else after the + as
suggested by Eli.

llvm-svn: 66370

1 files changed, 5 insertions, 1 deletions

diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 79be1625209..6c4176720af 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -3479,10 +3479,14 @@ QualType Sema::CheckAssignmentOperands(Expr *LHS, Expr *&RHS,
            UO->getOpcode() == UnaryOperator::Minus) &&
           Loc.isFileID() && UO->getOperatorLoc().isFileID() &&
           // Only if the two operators are exactly adjacent.
-          Loc.getFileLocWithOffset(1) == UO->getOperatorLoc())
+          Loc.getFileLocWithOffset(1) == UO->getOperatorLoc() &&
+          // And there is a space or other character before the subexpr of the
+          // unary +/-.  We don't want to warn on "x=-1".
+          Loc.getFileLocWithOffset(2) != UO->getSubExpr()->getLocStart()) {
         Diag(Loc, diag::warn_not_compound_assign)
           << (UO->getOpcode() == UnaryOperator::Plus ? "+" : "-")
           << SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc());
+      }
     }
   } else {
     // Compound assignment "x += y"