clang

btw, -Wpessimizing-move is included in clang's -Wall warnings. clang's warning documentation is poor, but the source code shows that -Wpessimizing-move and -Wredundant-move are included in -Wmove, which is included in -Wmost, which is included in -Wall: https://github.com/llvm-mirror/clang/blob/master/include/cla...

It's actually quite messy for C as well. I guess I should qualify that: it's messy for C as used in practice as well. #pragma weak, asm labels, always_inline, debug information, attribute regparm, inline assembly, etc... All of this is doable via incremental lowering from the AST (this is how clang does it) but it is fairly painful. Even the relatively banal: enum e; void (*fp)(enum e); enum e { v = 1ULL << 32 }; results in quite a bit of gymnastics! (https://github.com/llvm-mirror/clang/blob/202433cccd87a4e7d1...)

clang has a -Weverything flag that, unlike "-Wall", will enable all compiler warnings. This includes possibly contradictory warnings. :) For new C code, -Weverything is a good place to start. Unlike gcc, clang does not have good documentation for its warning options. The best sources I've found are the clang code itself (https://github.com/llvm-mirror/clang/blob/master/include/cla...) and http://fuckingclangwarnings.com/.