[Clang] Fix build after 141058

Fix incorrect static assert on some platforms

Author: cor3ntin

clang/lib/AST/Expr.cpp

@@ -1470,8 +1470,8 @@ static unsigned SizeOfCallExprInstance(Expr::StmtClass SC) {
 
 // changing the size of SourceLocation, CallExpr, and
 // subclasses requires careful considerations
-static_assert(sizeof(SourceLocation) == 4 && sizeof(CXXOperatorCallExpr) == 32,
-              "we assume CXXOperatorCallExpr is 32 bytes");
+static_assert(sizeof(SourceLocation) == 4 && sizeof(CXXOperatorCallExpr) <= 32,
+              "we assume CXXOperatorCallExpr is at most 32 bytes");
 
 CallExpr::CallExpr(StmtClass SC, Expr *Fn, ArrayRef<Expr *> PreArgs,
                    ArrayRef<Expr *> Args, QualType Ty, ExprValueKind VK,