build: handle output of localized gcc or clang

Before this commit, we used to scan the output of `$CC -v` for strings like
"gcc version x.y.z".

It was pointed out that this approach fails with localized versions of gcc
because those print (for example) "gcc versión x.y.z".

Use the output of `$CC --version` instead and only look at the first line.

configure

@@ -262,22 +262,24 @@ def host_arch():
 def target_arch():
   return host_arch()
 
+
 def compiler_version():
-  try:
-    proc = subprocess.Popen(CC.split() + ['-v'], stderr=subprocess.PIPE)
-  except OSError:
-    return (False, False, None)
-  lines = proc.communicate()[1].split('\n')
-  version_line = None
-  for i, line in enumerate(lines):
-    if 'version' in line:
-      version_line = line
-  if not version_line:
-    return (False, False, None)
-  version = version_line.split("version")[1].strip().split()[0].split(".")
-  if not version:
-    return (False, False, None)
-  return ('LLVM' in version_line, 'clang' in CC, tuple(version))
+  proc = subprocess.Popen(CC.split() + ['--version'], stdout=subprocess.PIPE)
+  version_line = proc.communicate()[0].split('\n')[0]
+
+  if 'clang' in version_line:
+    version, is_clang = version_line.split()[2], True
+  elif 'gcc' in version_line:
+    version, is_clang = version_line.split()[-1], False
+  else:
+    raise Exception(
+      'Unknown compiler. Please open an issue at ' +
+      'https://github.com/joyent/node/issues and ' +
+      'include the output of `%s --version`' % CC)
+
+  version = tuple(map(int, version.split('.')))
+  return (version, is_clang)
+
 
 def configure_node(o):
   # TODO add gdb
@@ -288,7 +290,7 @@ def configure_node(o):
   o['variables']['target_arch'] = options.dest_cpu or target_arch()
   o['default_configuration'] = 'Debug' if options.debug else 'Release'
 
-  is_llvm, is_clang, cc_version = compiler_version()
+  cc_version, is_clang = compiler_version()
 
   # turn off strict aliasing if gcc < 4.6.0 unless it's llvm-gcc
   # see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45883