diff --git a/clang/lib/Basic/Diagnostic.cpp b/clang/lib/Basic/Diagnostic.cpp
index c98fa6ebf817bd..661eabf9bc7cbb 100644
--- a/clang/lib/Basic/Diagnostic.cpp
+++ b/clang/lib/Basic/Diagnostic.cpp
@@ -40,9 +40,6 @@
 
 using namespace clang;
 
-static_assert(sizeof(DiagnosticBuilder) <= 2 * sizeof(void *),
-              "DiagnosticBuilder should be small, see class doc comments");
-
 const DiagnosticBuilder &clang::operator<<(const DiagnosticBuilder &DB,
                                            DiagNullabilityKind nullability) {
   StringRef string;