This website allows you to type in source code and see generated assembler code output by a number of different compilers and with your choice of command line switches so you can see the effect of optimisation options etc. There are umpteen versions of GCC, Clang / LLVM and Intel C++.
As well as having taken a look at the code generated by a range of C / C++ compilers, I have been trying out the D programming language. I love it, much prefer to C++ on the whole (its aim is to be a better C++).
- for D compilers