Add a snapshot of flutter/engine/src/build to our sdk

build/compiler_version.py

Index: build/compiler_version.py
diff --git a/build/compiler_version.py b/build/compiler_version.py
new file mode 100755
index 0000000000000000000000000000000000000000..05faf54454df5db32de33fddf0bf5723b297ebd8
--- /dev/null
+++ b/build/compiler_version.py
@@ -0,0 +1,143 @@
+#!/usr/bin/env python
+# Copyright (c) 2012 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Compiler version checking tool for gcc
+
+Print gcc version as XY if you are running gcc X.Y.*.
+This is used to tweak build flags for gcc 4.4.
+"""
+
+import os
+import re
+import subprocess
+import sys
+
+
+compiler_version_cache = {}  # Map from (compiler, tool) -> version.
+
+
+def Usage(program_name):
+  print '%s MODE TOOL' % os.path.basename(program_name)
+  print 'MODE: host or target.'
+  print 'TOOL: assembler or compiler or linker.'
+  return 1
+
+
+def ParseArgs(args):
+  if len(args) != 2:
+    raise Exception('Invalid number of arguments')
+  mode = args[0]
+  tool = args[1]
+  if mode not in ('host', 'target'):
+    raise Exception('Invalid mode: %s' % mode)
+  if tool not in ('assembler', 'compiler', 'linker'):
+    raise Exception('Invalid tool: %s' % tool)
+  return mode, tool
+
+
+def GetEnvironFallback(var_list, default):
+  """Look up an environment variable from a possible list of variable names."""
+  for var in var_list:
+    if var in os.environ:
+      return os.environ[var]
+  return default
+
+
+def GetVersion(compiler, tool):
+  tool_output = tool_error = None
+  cache_key = (compiler, tool)
+  cached_version = compiler_version_cache.get(cache_key)
+  if cached_version:
+    return cached_version
+  try:
+    # Note that compiler could be something tricky like "distcc g++".
+    if tool == "compiler":
+      compiler = compiler + " -dumpversion"
+      # 4.6
+      version_re = re.compile(r"(\d+)\.(\d+)")
+    elif tool == "assembler":
+      compiler = compiler + " -Xassembler --version -x assembler -c /dev/null"
+      # Unmodified: GNU assembler (GNU Binutils) 2.24
+      # Ubuntu: GNU assembler (GNU Binutils for Ubuntu) 2.22
+      # Fedora: GNU assembler version 2.23.2
+      version_re = re.compile(r"^GNU [^ ]+ .* (\d+).(\d+).*?$", re.M)
+    elif tool == "linker":
+      compiler = compiler + " -Xlinker --version"
+      # Using BFD linker
+      # Unmodified: GNU ld (GNU Binutils) 2.24
+      # Ubuntu: GNU ld (GNU Binutils for Ubuntu) 2.22
+      # Fedora: GNU ld version 2.23.2
+      # Using Gold linker
+      # Unmodified: GNU gold (GNU Binutils 2.24) 1.11
+      # Ubuntu: GNU gold (GNU Binutils for Ubuntu 2.22) 1.11
+      # Fedora: GNU gold (version 2.23.2) 1.11
+      version_re = re.compile(r"^GNU [^ ]+ .* (\d+).(\d+).*?$", re.M)
+    else:
+      raise Exception("Unknown tool %s" % tool)
+
+    # Force the locale to C otherwise the version string could be localized
+    # making regex matching fail.
+    env = os.environ.copy()
+    env["LC_ALL"] = "C"
+    pipe = subprocess.Popen(compiler, shell=True, env=env,
+                            stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+    tool_output, tool_error = pipe.communicate()
+    if pipe.returncode:
+      raise subprocess.CalledProcessError(pipe.returncode, compiler)
+
+    parsed_output = version_re.match(tool_output)
+    result = parsed_output.group(1) + parsed_output.group(2)
+    compiler_version_cache[cache_key] = result
+    return result
+  except Exception, e:
+    if tool_error:
+      sys.stderr.write(tool_error)
+    print >> sys.stderr, "compiler_version.py failed to execute:", compiler
+    print >> sys.stderr, e
+    return ""
+
+
+def main(args):
+  try:
+    (mode, tool) = ParseArgs(args[1:])
+  except Exception, e:
+    sys.stderr.write(e.message + '\n\n')
+    return Usage(args[0])
+
+  ret_code, result = ExtractVersion(mode, tool)
+  if ret_code == 0:
+    print result
+  return ret_code
+
+
+def DoMain(args):
+  """Hook to be called from gyp without starting a separate python
+  interpreter."""
+  (mode, tool) = ParseArgs(args)
+  ret_code, result = ExtractVersion(mode, tool)
+  if ret_code == 0:
+    return result
+  raise Exception("Failed to extract compiler version for args: %s" % args)
+
+
+def ExtractVersion(mode, tool):
+  # Check if various CXX environment variables exist and use them if they
+  # exist. The preferences and fallback order is a close approximation of
+  # GenerateOutputForConfig() in GYP's ninja generator.
+  # The main difference being not supporting GYP's make_global_settings.
+  environments = ['CXX_target', 'CXX']
+  if mode == 'host':
+    environments = ['CXX_host'] + environments;
+  compiler = GetEnvironFallback(environments, 'c++')
+
+  if compiler:
+    compiler_version = GetVersion(compiler, tool)
+    if compiler_version != "":
+      return (0, compiler_version)
+  return (1, None)
+
+
+if __name__ == "__main__":
+  sys.exit(main(sys.argv))