Remove Xcode dependence from ENV.rb

Fixes #7329.
Fixes #7269.
Fixes #7236.

Also quite a lot of tidy. This should all work fine.

I think we only started referring into xcode_prefix because LLVM used to not
be linked into /usr/bin. But for sure this is no longer true. If someone out
there doesn't link cc etc. into /usr/bin then I guess we can revise this patch
but it's not something we officially supported before, it was just an
accident.

I added a test step in the init code so that a working compiler will always be
selected. This is mainly a fallback for old Xcodes. Though a comment in
another area of the code suggested Xcode 3 on 10.5 doesn't have LLVM so…

1 files changed, 12 insertions, 29 deletions

diff --git a/Library/Homebrew/extend/ENV.rb b/Library/Homebrew/extend/ENV.rb
index b894c000d..5b9c13125 100644
--- a/Library/Homebrew/extend/ENV.rb
+++ b/Library/Homebrew/extend/ENV.rb
@@ -27,6 +27,10 @@ module HomebrewEnvExtension
       when :gcc then self.gcc
     end
 
+    # we must have a working compiler!
+    ENV['CC']  = '/usr/bin/cc'  unless File.exist? ENV['CC']
+    ENV['CXX'] = '/usr/bin/c++' unless File.exist? ENV['CXX']
+
     # In rare cases this may break your builds, as the tool for some reason wants
     # to use a specific linker. However doing this in general causes formula to
     # build more successfully because we are changing CC and many build systems
@@ -111,50 +115,29 @@ module HomebrewEnvExtension
   end
 
   def gcc_4_0_1
-    self['CC'] = self['LD'] = '/usr/bin/gcc-4.0'
+    self['CC'] = '/usr/bin/gcc-4.0'
     self['CXX'] = '/usr/bin/g++-4.0'
-    self.O3
+    remove_from_cflags '-O4'
     remove_from_cflags '-march=core2'
     remove_from_cflags %r{-msse4(\.\d)?}
   end
   alias_method :gcc_4_0, :gcc_4_0_1
 
   def gcc
-    if MacOS.xcode_version < '4'
-      self['CC'] = '/usr/bin/cc'
-      self['CXX'] = '/usr/bin/c++'
-    elsif MacOS.xcode_version >= '4.2'
-      # Apple stopped adding the -4.2 suffixes
-      self['CC']  = "#{MacOS.xcode_prefix}/usr/bin/gcc"
-      self['CXX']  = "#{MacOS.xcode_prefix}/usr/bin/g++"
-    else
-      # With Xcode4 cc, c++, gcc and g++ are actually symlinks to llvm-gcc
-      self['CC']  = "#{MacOS.xcode_prefix}/usr/bin/gcc-4.2"
-      self['CXX'] = "#{MacOS.xcode_prefix}/usr/bin/g++-4.2"
-    end
+    self['CC']  = "/usr/bin/gcc-4.2"
+    self['CXX'] = "/usr/bin/g++-4.2"
     remove_from_cflags '-O4'
   end
   alias_method :gcc_4_2, :gcc
 
   def llvm
-    if MacOS.xcode_version < '4'
-      self.gcc
-    elsif MacOS.xcode_version < '4.1'
-      self['CC'] = "#{MacOS.xcode_prefix}/usr/bin/llvm-gcc"
-      self['CXX'] = "#{MacOS.xcode_prefix}/usr/bin/llvm-g++"
-    else
-      self['CC'] = '/usr/bin/cc'
-      self['CXX'] = '/usr/bin/c++'
-    end
+    self['CC']  = "/usr/bin/llvm-gcc"
+    self['CXX'] = "/usr/bin/llvm-g++"
   end
 
   def clang
-    if MacOS.xcode_version > '4'
-      self['CC'] = "#{MacOS.xcode_prefix}/usr/bin/clang"
-      self['CXX'] = "#{MacOS.xcode_prefix}/usr/bin/clang++"
-    else
-      self.gcc
-    end
+    self['CC']  = "/usr/bin/clang"
+    self['CXX'] = "/usr/bin/clang++"
   end
 
   def fortran