[LLVMdev] [cfe-dev] New libc++ LLVM Subproject

[Duncan Sands]

Hi Howard

>                  compile time          run time
>                ----------------    ----------------
>                libstdc++ libc++    libstdc++ libc++
>
> g++-4.2 -O3      0.62    0.96        23       5
> clang++ -O3      0.66    0.80        21       5
>
> Since compile times are usually more important with non-opitimzed builds I computed the same table at -O0:
>
>                  compile time          run time
>                ----------------    ----------------
>                libstdc++ libc++    libstdc++ libc++
>
> g++-4.2 -O0      0.48    .76         186      5
> clang++ -O0      0.46    .70         261      5

it seems odd that the libc++ runtime does not change when compiling at -O0.
Why is that?

Best wishes,

Duncan.