[clang] [clang-repl] Lay the foundation of pretty printing for C. (PR #89811)

[David Spickett via cfe-commits]

DavidSpickett wrote:

I have bisected a 32 bit Arm failure down to this change: https://lab.llvm.org/buildbot/#/builders/245/builds/25526

Is it possible that something in this code is truncating a value when interpreting types intended for a 64 bit system, on a 32 bit system? I don't see this failure on any of our Arm64 buildbots.

https://github.com/llvm/llvm-project/pull/89811