c++11 std::unique_ptr error cmake 3.11.3 bootstrap

Question

I am trying to bootstrap cmake 3.11.3 on Ubuntu 16.04.4 LTS xenial.

I have upgrade my gnu g++ compiler as follows:

> $ g++ --version
g++ (Ubuntu 8.1.0-5ubuntu1~16.04) 8.1.0 Copyright (C) 2018 Free
Software Foundation, Inc. This is free software; see the source for 
copying conditions.  There is NO warranty; not even for MERCHANTABILITY 
or FITNESS FOR A PARTICULAR PURPOSE.

And manually re-pointed the symbolic links:

$ ll /usr/bin/*g++*
lrwxrwxrwx 1 root root       5 Jun  8 16:57 /usr/bin/g++ -> g++-8*
-rwxr-xr-x 1 root root  919832 Apr 24 15:02 /usr/bin/g++-5*
lrwxrwxrwx 1 root root      22 Jun  6 04:26 /usr/bin/g++-8 -> x86_64-linux-gnu-g++-8*
lrwxrwxrwx 1 root root      22 Jun  8 16:58 /usr/bin/x86_64-linux-gnu-g++ -> x86_64-linux-gnu-g++-8*
lrwxrwxrwx 1 root root       5 Apr 24 15:02 /usr/bin/x86_64-linux-gnu-g++-5 -> g++-5*
-rwxr-xr-x 1 root root 1071984 Jun  6 04:26 /usr/bin/x86_64-linux-gnu-g++-8*

However, I get the following error in the configuration of cmake:

$ sudo ./bootstrap 
---------------------------------------------
CMake 3.11.3, Copyright 2000-2018 Kitware, Inc. and Contributors
Found GNU toolchain
C compiler on this system is: gcc       
C++ compiler on this system is: g++          
Makefile processor on this system is: make
g++ has setenv
g++ has unsetenv
g++ does not have environ in stdlib.h
g++ has stl wstring
g++ has <ext/stdio_filebuf.h>
---------------------------------------------
make: Warning: File 'Makefile' has modification time 2.3 s in the future
make: 'cmake' is up to date.
make: warning:  Clock skew detected.  Your build may be incomplete.
loading initial cache file /mnt/ganymede/user/gpeytavi/srv_admin/software/cmake-3.11.3/Bootstrap.cmk/InitialCacheFlags.cmake
CMake Error at CMakeLists.txt:92 (message):
  The C++ compiler does not support C++11 (e.g.  std::unique_ptr).


-- Configuring incomplete, errors occurred!
See also "/mnt/ganymede/user/gpeytavi/srv_admin/software/cmake-3.11.3/CMakeFiles/CMakeOutput.log".
See also "/mnt/ganymede/user/gpeytavi/srv_admin/software/cmake-3.11.3/CMakeFiles/CMakeError.log".
---------------------------------------------
Error when bootstrapping CMake:
Problem while running initial CMake
---------------------------------------------

Any idea why I get a c++11 std::unique_ptr non-compliant error?

Answer 1

In my case, the issue is because of the folder where I have CMake source code is in a mounted directory (in fact my entire rootfs is mounted over NFS) So, I looked in 'mount' command output and selected '/run/user/1000' location as a local location as this is mounted using tmpfs and moved my CMake source code to this location. with this, ./bootstrap && make && sudo make install executed successfully.