Conda: update gcc and isl error

Question

I have installed conda 4.3.22 and want to update conda gcc from 4.8.5 to 6.2.0. By using the following command I am getting an error because of the isl version. However, by trying to install a newer version of isl I am getting an error because of the gcc version. This is a rather dumb problem but I am not sure on how to get around it.

$ conda install -c salford_systems gcc-6=6.2.0
Fetching package metadata ...........
Solving package specifications: 

PackageNotFoundError: Dependency missing in current linux-64 channels: 
  - gcc-6 6.2.0* -> isl >=0.17,<=0.17.1


$ conda install -c conda-forge isl=0.17.1
Fetching package metadata ...........
Solving package specifications: .

UnsatisfiableError: The following specifications were found to be in conflict:
  - gcc -> isl >=0.10,<=0.14
  - isl 0.17.1*
Use "conda info <package>" to see the dependencies for each package.

Edit 1: As it was pointed out in the comments by darthbith, a combined command is not working and throws the following error:

$ conda install -c conda-forge -c salford_systems gcc-6=6.2.0 isl=0.17.1
Fetching package metadata .............
Solving package specifications: .

UnsatisfiableError: The following specifications were found to be in conflict:
  - gcc -> isl 0.12.*
  - gcc-6 6.2.0*
Use "conda info <package>" to see the dependencies for each package.

Do I understand it correct, that gcc and gcc-6 are different packages of which both require a different version of isl and thus leading to my problem? I only would need a newer version of gcc which supports GLIBCXX_3.4.21.

Thanks in advance.

Can you try specifying both channels in the install command? `conda install -c conda-forge -c salford_systems gcc-6=6.2.0 isl=0.17.1` — darthbith, Jun 27 '17 at 13:09
Thank you for your answer @darthbith. Unfortunately your command is not working, please see Edit 1 for details. — Icarus, Jun 28 '17 at 10:48
Yes, it appears that `gcc` and `gcc-6` are different packages. I'm not sure how to solve all these dependencies, you'll have to use `conda info `, as suggested in the error, to sort out which ones will work — darthbith, Jun 28 '17 at 12:25

score 2 · Accepted Answer · answered Jul 05 '17 at 11:10

I was able to solve my problem, thank you darthbith for helping me out.

Since gcc and gcc-6 are in fact two different packages, the solution was to delete gcc. After that, I had to update isl before I could install gcc-6. The commands used were:

conda uninstall gcc
conda install -c conda-forge isl=0.17.1
conda install -c salford_systems gcc-6=6.2.0

Conda: update gcc and isl error

1 Answers1