3 ms·

I think the compiler still needs to know that the value might be modified from the outside. Otherwise it might optimize the read operation away from the codepat

I think the compiler still needs to know that the value might be modified from the outside. Otherwise it might optimize the read operation away from the codepath.

simcop2387 7y ago
You'd have to do all the reads in ASM too then, but it would still be possible. It'd be terrible ergonomically.
- saagarjha 7y ago
  At that point you’re really not writing C++ at all; you’re writing assembly in a .cpp file.
  - m0zg 7y ago
    Nah. You could just define an inline function that'd do volatile read or write of a particular type. You don't have to hit assembly all the time.
srfilipek 7y ago
Yes, that is part of creating inline assembly in C or C++ code: http://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html http://gcc.gnu.org/onlinedocs/gcc/Extended-Asm.html