configure needs C++14 support but gcc -v = 4.9.3

Question

I am currently in the process of compiling graph-tool v1.13 from the Git version. I have managed to generate the configure file from autogen.sh but am now running into trouble.

Running ./configure I receive the message:

checking whether g++ supports C++14 features by default... no
checking whether g++ supports C++14 features with -std=gnu++14... no
checking whether g++ supports C++14 features with -std=gnu++0x... no
configure: error: *** A compiler with support for C++14 language features is required.

I have checked gcc -v and g++ -v and receive the response gcc version 4.9.3 (Ubuntu 4.9.3-8ubuntu2~14.04). To my knowledge this should support C++14 so where am I going wrong? I am running Ubuntu 14.04.

Solution 1

Try perhaps

./configure CXX='g++-5'

after having installed some GCC 5

Solution 2

gcc 4.9.3 supports C++14, but the correct compiler flag is '-std=c++14'

Comments

[DevSolar]

@P-M: configure would mean "the command configure found in the command path" -- which does not exist, leading to the error message you mentioned. ./configure means "the command configure in the current directory"...