https://doc.qt.io/QtForMCUs/qul-platform-stackallocator.html
Qul::Platform::StackAllocator Class | Qt Quick Ultralite Platform Porting Guide | Qt for MCUs 2.12.1
Provides a simple memory allocator for functions that might temporarily require some extra memory for caching.
https://rapidjson.org/classrapidjson_1_1_generic_document.html
RapidJSON: rapidjson::GenericDocument Encoding, Allocator, StackAllocator Class Template...
rapidjsonencodingallocatorclasstemplate