gfortran error installing eigen

[dlaz]

Trying to install eigen on a machine I just upgraded to Lion, and it errors out complaining that gfortran is broken. I've tried using both the version of gfortran that was already installed (not sure where it came from), and the version installed by homebrew.

$ file `which gfortran`
/usr/local/bin/gfortran: Mach-O universal binary with 2 architectures
/usr/local/bin/gfortran (for architecture i386):    Mach-O executable i386
/usr/local/bin/gfortran (for architecture x86_64):  Mach-O 64-bit executable x86_64

Install output: https://gist.github.com/1707233

[Sharpie]

Builds fine for me.

Trying to install eigen on a machine I just upgraded to Lion,

If you upgraded from Snow Leopard, make sure both Xcode and the gfortran formula are re-installed. Specifically, in the error message:

i686-apple-darwin10-gfortran-4.2.1: error trying to exec 'f951': execvp: No such file or directory

The GFortran compiler should read darwin11, not darwin10.

[dlaz]

I did indeed just upgrade from Snow Leopard. I just reinstalled xcode from the installer I downloaded from the app store this morning, with the same results.

In /Developer/usr/bin, I have darwin11 g++ and gcc, but no gfortran at all.

[Sharpie]

I did indeed just upgrade from Snow Leopard. I just reinstalled xcode from the installer I downloaded from the app store this morning, with the same results.

Allright. That's one check on the list. Now about the other one: did you also re-install the gfortran formula?

[dlaz]

Yep, reinstalled the gfortran formula.

[dlaz]

export FC=which gfortran`` seems to have fixed it.

[samueljohn]

I cannot reproduce this on lion. But I am no "eigen" user. eigen seems not even to depend on gfortran. Strange.

   brew remove gfortran
   brew remove eigen
   brew install eigen

This seems to work fine. Have you different optional backends than me?

    -- Build type:        Release
    -- Enabled backends:   Qt4 support, 
    -- Disabled backends:  GSL,  Cholmod,  UmfPack,  SuperLU,  GoogleHash,  Adolc,  MPFR C++,  fftw,  OpenGL,  GSL, 

From your output it seems as if /usr/bin/gfortran was used. I removed my gfortran and still it compiles.
Where does which gfortran point to on your system?
Have you done: brew update followed by brew upgrade ?

@dlaz what do you think?

[samueljohn]

Ok, when I remove gfortran during configuration brew install -v eigen reports:
-- The Fortran compiler identification is unknown
but apparently succeeds installation. So is gfortran optional?
If gfortran is really needed by this formula, I think there should be ENV.fortran added to it, right @Sharpie?

[samueljohn]

Having gfortran installed by brew install gfortran then leads to:

    -- The Fortran compiler identification is GNU
    -- Check for working Fortran compiler: /usr/local/bin/gfortran
    -- Check for working Fortran compiler: /usr/local/bin/gfortran  -- works
    -- Detecting Fortran compiler ABI info
    -- Detecting Fortran compiler ABI info - done
    -- Checking whether /usr/local/bin/gfortran supports Fortran 90
    -- Checking whether /usr/local/bin/gfortran supports Fortran 90 -- yes

@dlaz, if you could try it again? Otherwise I would suggest to close this issue.

[dlaz]

I was all updated and still seeing this problem. It seems like there was something weird about my configuration that was causing it to look for gfortran in the wrong place. Why it wanted gfortran in the first place is another issue...

[samueljohn]

So now it is working or you do not care about it any more, I assume. I, too, think there is something wrong with your configuration but I have no clue what.

Or would you mind to remove gfortran, install it again and then brew install eigen?
Perhaps brew doctor tells something more. (I assume you have updated and upgraded brew)

[dlaz]

As I mentioned before, setting my FC environment variable fixed the problem, and eigen installs properly now.

I've already tried reinstalling homebrew's version of gfortran, which had no effect, and brew doctor shows no problems.

[samueljohn]

Ok, thanks :-)
I am running out of options anyways. (Besides pointing to the obvious things and asking for brew --config.)

[Sharpie]

Ahh.. this makes more sense now that I see eigen is not using ENV.gfortran. Making that call in the install block sets things like FC which is what @dlaz is currently doing manually.

[samueljohn]

@dlaz you see, @Sharpie is the pro :-)

[Sharpie]

Oops. Corrected to ENV.fortran instead of ENV.gfortran. My brain does not work right without caffeine.

[pierrelb]

Still running into problems with this, but see the discussion at #10240 which reveals fortran is not required anyway. I was able to install eigen using:

FC='' brew install eigen