Re: Requiring C++11 in configure.ac

[Rik]

On 06/20/2017 01:41 PM, address@hidden wrote:
> Subject: > Re: Requiring C++11 in configure.ac > From: > "John W. Eaton" <address@hidden> > Date: > 06/20/2017 10:22 AM > To: > address@hidden > CC: > address@hidden > List-Post: > <mailto:address@hidden> > Content-Transfer-Encoding: > 7bit > Precedence: > list > MIME-Version: > 1.0 > References: > <address@hidden> <address@hidden> > In-Reply-To: > <address@hidden> > Message-ID: > <address@hidden> > Content-Type: > text/plain; charset=utf-8; format=flowed > Message: > 4 > > On 06/20/2017 01:20 PM, Mike Miller wrote: >> On Tue, Jun 20, 2017 at 09:14:01 -0700, Rik wrote: >>> We now require C++11 to build Octave, but is there a test for that in >>> configure.ac? >> >> The configure script has tests for C++11 features and adds the options >> to the compiler command line if needed to enable those, but there is no >> error if those tests fail, it just falls back to whatever flavor of C++ >> the compiler handles by default. > > Right, those tests are added by the std-gnu11 module from gnulib. > > jwe
So maybe after gnulib bootstrap has occurred and the compiler and flags have been determined we should check the version with

AC_LANG_PUSH(C++)
AC_PREPROC_IFELSE([AC_LANG_SOURCE([[
                   #if (__cplusplus < 201103L)
                   #  error "Octave requires a C++11 compiler"
                   #endif
                  ]], [])],
                  [],
                  [AC_MSG_ERROR([Octave requires a C++11 compiler])])
AC_LONG_POP(C++)

--Rik

p.s. Actually, probably need to push/pop C++ as the lang before this