configure fails to detect too-old ruby and fails on syntax error

[jeffhammond]

I got this very strange error:

[jrhammon@esgmonster github]$ ./configure 
./configure:72: syntax error, unexpected kNOT
  if not(opt.cc) && not(opt.cxx)
                       ^
./configure:74: syntax error, unexpected kEND, expecting $end

I had a crazy idea to look at configure, and noticed that it requires Ruby 1.9.3, while I have only 1.8.7:

[jrhammon@esgmonster github]$ ruby --version
ruby 1.8.7 (2013-06-27 patchlevel 374) [x86_64-linux]

I am confused as to why the script cannot figure this out via:

# verify we're running a supported ruby version
required_version = '1.9.3'
rv_arr = required_version.split('.').map{ |s| s.to_i }
av_arr = RUBY_VERSION.split('.').map{ |s| s.to_i }
if (av_arr <=> rv_arr) < 0
  abort("Ruby version #{required_version} required, but found #{RUBY_VERSION}. Aborting.")
end

Unfortunately, I am too stupid and know too little Ruby to even debug this problem, because none of my attempts to write out debug info to the terminal have any effect.

[jeffhammond]

The configure script works fine if I remove the following lines:

[jrhammon@esgmonster github]$ git diff
diff --git a/configure b/configure
index 96a46c7..a214965 100755
--- a/configure
+++ b/configure
@@ -68,21 +68,10 @@ end
 # Xcode generator must have CC set to a version of Clang, and must have a corresponding plugin
 # see github.com/bholt/Clang-Head.xcplugin for an example

-### unless opt.generator =~ /Xcode/ # (Xcode generator currently chokes on other compilers...)
-  if not(opt.cc) && not(opt.cxx)
-    abort("Must specify C compiler (either use '--cc=' or '--cxx=' flags, or set the environment variables CC & CXX\nhint: if the compiler you want is on your PATH, you can do: --cc=$(which gcc)...")
-  end
-### end
-
 if opt.tracing && opt.profiling
   abort "Please choose one of profiling or tracing."
 end

-      
-if opt.tracing && not(opt.vampir) && opt.third_party
-  opt.vampir = opt.third_party
-end
-
 # verify we're on a 64-bit machine
 case `uname -m`
 when /x86_64/

[nelsonje]

The real solution here is to rewrite the configure script in bash; we don't need to use Ruby here (or anywhere else in the project). This is on my list, but it'll be a while until I get to it.

[jeffhammond]

I stopped using configure and am now invoking CMake directly to avoid Ruby issues.