diff --git a/src/corelib/tools/qchar.h b/src/corelib/tools/qchar.h
index a0c82dba05..84df8accc5 100644
--- a/src/corelib/tools/qchar.h
+++ b/src/corelib/tools/qchar.h
@@ -89,8 +89,10 @@ public:
 #if defined(Q_COMPILER_UNICODE_STRINGS)
     Q_DECL_CONSTEXPR QChar(char16_t ch) Q_DECL_NOTHROW : ucs(ushort(ch)) {} // implicit
 #endif
-#if defined(Q_OS_WIN) || defined(Q_CLANG_QDOC)
+#if defined(Q_OS_WIN)
     Q_STATIC_ASSERT(sizeof(wchar_t) == sizeof(ushort));
+#endif
+#if defined(Q_OS_WIN) || defined(Q_CLANG_QDOC)
     Q_DECL_CONSTEXPR QChar(wchar_t ch) Q_DECL_NOTHROW : ucs(ushort(ch)) {} // implicit
 #endif