Brew: C compiler shim doesn't respect PATH

[dlukes]

I have two versions of gcc installed on my machine, one in /usr/bin and another in ~/.local/bin. Even though my PATH puts the .local directory before the usr one, brew install still wants to use the (outdated) gcc under /usr/bin.

The only way I can force brew to use the intended gcc under ~/.local/bin is to change the ~/.linuxbrew/Homebrew/Library/Homebrew/shims/linux/super/cc shim script to a soft link to ~/.local/bin/gcc.

I'm not quite sure what the shims are for, but I suppose this is not desired behavior? If possible, I think the user should be able to decide which compiler will be used in an intuitive way, i.e. by manipulating the PATH.

[sjackman]

Linuxbrew selects the most recent compiler that it knows of. It searches for compilers named gcc-4.x or gcc-x. Best solution is to brew install gcc
Otherwise see https://github.com/Linuxbrew/brew/wiki/Symlink-GCC

[dlukes]

Thanks for the link! The newer compiler was named gcc-5.3, so that might have been the problem...? At any rate I still think it's a bit counterintuitive...

Best solution is to brew install gcc

... especially since brew installing gcc was actually what I was trying to do at the time, but that required installing glibc first, which I couldn't compile with the older (system) gcc compiler, so that's why I was trying to get brew to use my custom gcc in the first place :)

Maybe it would be nice to put a link to the wiki page in the instructions displayed after installing brew? Or in the tips which are displayed when glibc / gcc installation fails -- something along the lines of "If you need to bootstrap brew with a custom version of gcc, this is how you do it: \

[sjackman]

The newer compiler was named gcc-5.3, so that might have been the problem...

Yep, it needs to be named gcc-5 and g++-5.

[sjackman]

but that required installing glibc first, which I couldn't compile with the older (system) gcc compiler

Here's a relevant issue:
https://github.com/Linuxbrew/homebrew-core/issues/4077#issuecomment-329636939

This problem is relatively recent, since we upgraded from glibc 2.19 to 2.23. I'm working on a better solution. It's a tricky one though.

[sjackman]

Here's instructions to install Linuxbrew on CentOS 6 without sudo. https://github.com/Linuxbrew/brew/wiki/CentOS6
Which distribution of Linux are you using?