I am trying to read LR and FP registers address. I have tried calling the __builtinXXX API’s as well as using assembly directly, using Arm cortex M0 and llvm/clang compiler, C language extension. All I get is zeros. Doesn’t make scense. Is there a special way to do this?
I found information regarding C++ classes but no C info. Can someone refer me please to the right info?