brew --config output improved if no GCC

Library/Homebrew/brew.h.rb

@@ -439,7 +439,11 @@ end
 
 def gcc_build
   `/usr/bin/gcc-4.2 -v 2>&1` =~ /build (\d{4,})/
+  if $1
     $1.to_i 
+  else
+    nil
+  end
 end
 
 def llvm_build

bin/brew

@@ -45,6 +45,7 @@ def dump_config
   bits = Hardware.bits
   cores = Hardware.cores_as_words
   llvm = llvm_build
+  gcc = gcc_build
   sha = `git rev-parse --verify HEAD`.chomp
   kernel_arch = `uname -m`.chomp
 
@@ -60,7 +61,7 @@ Hardware: #{cores}-core #{bits}-bit #{Hardware.intel_family}
 OS X: #{MACOS_FULL_VERSION}
 Kernel Architecture: #{kernel_arch}
 Ruby: #{RUBY_VERSION}-#{RUBY_PATCHLEVEL}
-GCC: 4.2 build #{gcc_build}
+GCC-4.2: #{gcc ? "build #{gcc}" : "N/A"}
 LLVM: #{llvm ? "build #{llvm}" : "N/A" }
 MacPorts or Fink? #{macports_or_fink_installed?}
 EOS