Downgrading gcc/g++ for use with mex

I'm running Matlab 2017a on an Ubuntu 16.04.2 LTS (xenial). The default gcc/g++ versions are 5.4.0 and Matlab only supports version 4.9.x.

Are there good suggestions on how to "downgrade" the g++/gcc versions so that I can have mex working OK?

Thanks,

Answer 1

[Amit Doshi]

Hello Karthik,

To change the compiler in the mex command, set the varname variable. varname for the gcc compiler is GCC, in uppercase letters. For example, if the currently supported gcc compiler is version 4.7, and it is installed in the /usr/bin/gcc-4.7 folder on your system, to build timestwo.c, type:

copyfile(fullfile(matlabroot,'extern','examples','refbook','timestwo.c'),'.','f')
mex -v GCC='/usr/bin/gcc-4.7' timestwo.c

Setting the compiler using the mex command does not change the system default compiler.

Also, refer the below link to downgrade GCC in Ubuntu:

https://askubuntu.com/questions/724872/downgrade-gcc-from-5-2-1-to-4-9-ubuntu-15-10