Ignore clang warning Wnontrivial-memaccess

[mayawarrier]

• Clang produces warning Wnontrivial-memaccess when memset is used on a non-trivially copyable type.
• Platform: Clang 20.0.0, Emscripten 1
• Warning log: warning_log.txt
• Locations where warnings are triggered:
  

[ocornut]

Thank you Maya for your report and PR!

I'm quite surprised it would happen in e.g. imgui_impl_metal.mm where the only memset() is for a class with a raw pointer. My guess is that memset() being inside a constructor, it makes the class non-trivial from Clang's pov.

My other surprise is that we do have an equivalent warning silencing for GCC:

#pragma GCC diagnostic ignored "-Wclass-memaccess"      // [__GNUC__ >= 8] warning: 'memset/memcpy' clearing/writing an object of type 'xxxx' with no trivial copy-assignment; use assignment or value-initialization instead

But this is used in more location than the files you touched, so that's curious. I'm merging for now.
Thanks!