> On Nov. 4, 2015, 1:02 a.m., Michael Hopcroft wrote: > > 3rdparty/libprocess/3rdparty/stout/include/stout/os/windows/stat.hpp, line > > 107 > > <https://reviews.apache.org/r/39803/diff/2/?file=1113684#file1113684line107> > > > > Is the enum+switch+unreachable a common pattern in stout? It seems that > > choosing to use an enume for follw, instead of a bool made this code much > > more complex. > > > > Also, this is the only use of UNREACHABLE(), so you could remove the > > #include if you reworked the function. > > > > Perhaps size() is an existing API in stout and you have no choice about > > its prototype? In that case, are you sure that your version of enum > > FollowSymlink is exactly the same as the one used in the Linux version. > > > > You would hate for someone on the Linux side to take a dependency on > > the order of the items inside the enum and find that you had changed that > > order. > > Joseph Wu wrote: > Yes, `UNREACHABLE` is commonly used in enum-switch statements. > > There is another pattern of excluding a `default` and adding a blurb like: > ``` > // NOTE: By not setting a default we leverage the compiler > // errors when the enumeration is augmented to find all > // the cases we need to provide. > ``` > (We do end up using `UNREACHABLE` anyway in some of those cases too.)
In light of https://issues.apache.org/jira/browse/MESOS-3754 I went and checked how often we actually add a `default` branch when we `switch` over enum values. This is the `clang-query` I used (which probably misses some cases of fall-through into `default`): match switchStmt(has(declRefExpr(hasType(enumDecl()))), has(compoundStmt(has(defaultStmt().bind("default"))))) After checking all stout tests, their includes, and similarly all libprocess `.cpp` files I could only find a single such case in `os::stat::size`. We *do use* `default` branches when switching over int values though; here the domain makes it impractical to enumerate all values ;) - Benjamin ----------------------------------------------------------- This is an automatically generated e-mail. To reply, visit: https://reviews.apache.org/r/39803/#review105007 ----------------------------------------------------------- On Nov. 16, 2015, 9:14 a.m., Alex Clemmer wrote: > > ----------------------------------------------------------- > This is an automatically generated e-mail. To reply, visit: > https://reviews.apache.org/r/39803/ > ----------------------------------------------------------- > > (Updated Nov. 16, 2015, 9:14 a.m.) > > > Review request for mesos, Artem Harutyunyan, Michael Hopcroft, Joris Van > Remoortere, and Joseph Wu. > > > Repository: mesos > > > Description > ------- > > Windows: Implemented stout/os/stat.hpp`. > > > Diffs > ----- > > 3rdparty/libprocess/3rdparty/stout/include/Makefile.am > a8c35c086ecae21701f6a720f25231c1b0d4e329 > > 3rdparty/libprocess/3rdparty/stout/include/stout/internal/windows/reparsepoint.hpp > PRE-CREATION > > 3rdparty/libprocess/3rdparty/stout/include/stout/internal/windows/symlink.hpp > PRE-CREATION > 3rdparty/libprocess/3rdparty/stout/include/stout/os/windows/stat.hpp > 675b2e712358a55b3580026936890eaf80e5af71 > 3rdparty/libprocess/3rdparty/stout/include/stout/windows.hpp > 1a7037d64afeedc340258c92067e95d1d3caa027 > > Diff: https://reviews.apache.org/r/39803/diff/ > > > Testing > ------- > > `make check` from autotools on Ubuntu 15. > `make check` from CMake on OS X 10.10. > Ran `check` project in VS on Windows 10. > > > Thanks, > > Alex Clemmer > >
