> Le 21 déc. 2015 à 01:55, Jonathan Wakely <jwakely.gcc@xxxxxxxxx> a écrit : > > On 20 December 2015 at 19:13, Akim Demaille <akim.demaille@xxxxxxxxx> wrote: >> Hi! >> >> I’m looking for a #if guard to enable/disable code using concepts-lite. > > As required by the Concepts TS, the compiler defines __cpp_concepts > when it supports concepts. Great, thanks! >> Also, the documentation about concepts seems to be about the previous attempts at concepts. >> >> https://gcc.gnu.org/onlinedocs/gcc/C_002b_002b-Concepts.html#C_002b_002b-Concepts >> >> And actually, I did not find the documentation for c++1z, nor even -std=c++14. > > https://gcc.gnu.org/onlinedocs/gcc/C-Dialect-Options.html Ah! Thanks. But then, I would suggest that this is misleading: the sections "Options Controlling C Dialect » and "Options Controlling C++ Dialect" are not as symmetrical as their names would imply. Maybe the C++ section could at least have an item about -std that points to the C documentation. > Also > https://gcc.gnu.org/projects/cxx1y.html > https://gcc.gnu.org/projects/cxx1z.html > > >> https://gcc.gnu.org/onlinedocs/gcc/Standards.html#index-std-60 My point here was that this page documents C++ up to C++11, and points to "Options Controlling C++ Dialect" for more information about C++ standards, whereas you just showed that it’s the page about C dialects that should be pointed to, and that there are many more options that what this section reports. >> >> Finally, one would expect to see documentation about -std in "Options Controlling C++ Dialect", since the corresponding about C documents -std for C. >> >> https://gcc.gnu.org/onlinedocs/gcc/C_002b_002b-Dialect-Options.html#C_002b_002b-Dialect-Options > > That's the documentation about -std in general, not -std for C. It > says "The following options control the dialect of C (or languages > derived from C, such as C++, …)" Yes, thanks for pointing this out. But I think that this is unfortunate. Maybe -std deserves a section on its own. I guess that gccgo, gnat and other also use this -std option, so even if the main documentation for GCC does not cover these languages, it would make sense to detach it from C. Say next to -x. This is just a suggestion, forget about it if it sounds stupid.
