[CLN-list] CLN switched to C++11

[Bruno Haible]

Jan Rheinländer wrote:
> the problem is not the MSVC compiler but the configure script. If you
> just remove the requirement from configure.ac, then it works fine. I
> always comment out the line
> 
> AX_CXX_COMPILE_STDCXX_11
> 
> and it works.

Right. Either comment it out, or don't request a C++11 compiler
as mandatory. I'm pushing this; with this, the configuration with MSVC
succeeds again.

diff --git a/configure.ac b/configure.ac
index c1a8a59..8a81007 100644
--- a/configure.ac
+++ b/configure.ac
@@ -90,7 +90,7 @@ AC_SUBST(CL_VERSION)
 dnl           checks for compiler characteristics
 dnl
 AC_LANG([C++])
-AX_CXX_COMPILE_STDCXX([11])
+AX_CXX_COMPILE_STDCXX([11], [ext], [optional])
 dnl
 CL_LONGLONG
                       dnl DEFS HAVE_LONGLONG