Hello, I'm experiencing a 50% slowdown with some code I'm working on when compiling with LTO enabled using gcc version 4.8.1 (Ubuntu/Linaro 4.8.1-10ubuntu8) (in C++). Another past post suggested compiling with -pg and checking LTO and non-LTO builds with gprof, but gcc doesn't seem to want to output a gmon.out. This is the first thing I'd like to solve? I have since profiled the program with callgrind, and am unable to see what could possibly be causing this kind of slowdown. I have modularised the code into separate translation units in such a way that I was anticipating being able to use LTO to improve performance. This is a bit of a blow for me that it is not achieving this purpose, but actually degrading performance. Kind regards, Troy
