Remove dependency on scan-build wrapper script for Clang analysis builds.

build/toolchain/clang_static_analyzer_wrapper.py

 #!/usr/bin/env python
-# Copyright 2016 The Chromium Authors. All rights reserved.
+# Copyright 2017 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.
 
-"""Invokes the Clang static analysis command using arguments provided on the
-command line.
+"""Adds an analysis build step to invocations of the Clang C/C++ compiler.
+
+Usage: clang_static_analyzer_wrapper.py <compiler> [args...]
 """
 
 import argparse
 import fnmatch
+import itertools
 import os
-import shutil
 import sys
-import tempfile
+import wrapper_utils
 
-import wrapper_utils
+# Flags used to enable analysis for Clang invocations.
+analyzer_enable_flags = [
+    '--analyze',
+    '-fdiagnostics-show-option'
+]
+
+# Clang flags specifying which checkers should be run.
+# The full list of checkers can be found at
+# https://clang-analyzer.llvm.org/available_checks.html.
+analyzer_option_flags = [
+      '-analyzer-output=text',
+      '-analyzer-opt-analyze-nested-blocks',
+      '-analyzer-eagerly-assume',
+      '-analyzer-checker=core',
+      '-analyzer-checker=unix',
+      '-analyzer-checker=deadcode',
+      '-analyzer-checker=cplusplus',
+]
 
 
 def main():
-  parser = argparse.ArgumentParser(description=__doc__)
-  parser.add_argument('--clang-cc-path',
-                      help='Path to the clang compiler.',
-                      metavar='PATH')
-  parser.add_argument('--clang-cxx-path',
-                      help='Path to the clang++ compiler',
-                      metavar='PATH')
-  parser.add_argument('--analyzer',
-                      help='Path to the language-specific Clang analysis tool.',
-                      required=True,
-                      metavar='PATH')
-  args, compile_args = parser.parse_known_args()
+  args = sys.argv[1:]
+  assert(args)
 
-  # Check that only one of --clang-cc-path or --clang-cxx-path are set.
-  assert ((args.clang_cc_path != None) != (args.clang_cxx_path != None))
+  # Interleave 'analyzer_option_flags' flags w/'-Xanalyzer' so that Clang
+  # passes them to the analysis tool.
+  # e.g. ['-analyzer-foo', '-analyzer-bar'] => ['-Xanalyzer', '-analyzer-foo',
+  #                                             '-Xanalyzer', '-analyzer-bar']
+  interleaved_analyzer_flags = reduce(
+      lambda x, y: x + ['-Xanalyzer', y], analyzer_option_flags, [])
 
-  is_cxx = args.clang_cxx_path != None
-  env = os.environ
-  env['CCC_ANALYZER_FORCE_ANALYZE_DEBUG_CODE'] = '0'
-  env['CCC_ANALYZER_OUTPUT_FORMAT'] = 'text'
-  clang_path = args.clang_cxx_path or args.clang_cc_path
-  if is_cxx:
-    env['CCC_CXX'] = clang_path
-    env['CLANG_CXX'] = clang_path
-  else:
-    env['CCC_CC'] = clang_path
-    env['CLANG'] = clang_path
+  returncode, stderr = wrapper_utils.CaptureCommandStderr(
+      wrapper_utils.CommandToRun(args + analyzer_enable_flags +
+                                 interleaved_analyzer_flags))
 
-  # TODO(kmarshall): Place the summarized output in a useful directory.
-  temp_dir = tempfile.mkdtemp()
-  try:
-    env['CCC_ANALYZER_HTML'] = temp_dir
-    returncode, stderr = wrapper_utils.CaptureCommandStderr(
-        wrapper_utils.CommandToRun([args.analyzer] + compile_args), env)
-    sys.stderr.write(stderr)
-    return returncode
-  finally:
-    shutil.rmtree(temp_dir)
+  # TODO(kmarshall): Post-process the analysis output and remove any errors for
+  # excluded files.

[Wez, 2017/02/03 19:27:54]

nit: Add a bug # :D

[Kevin M, 2017/02/06 17:39:56]

Done.

+  sys.stderr.write(stderr)
 
-if __name__ == "__main__":
+  if returncode != 0:
+    # The analyzer is a little buggy and can crash midway through an AST parse
+    # on otherwise buildable code.
+    # If it fails, we should recover gracefully and continue with the build.
+    sys.stderr.write(
+        'WARNING: Clang analyzer exited with return code %d.\n' % (returncode))
+
+  # Build the object file.
+  returncode, stderr = wrapper_utils.CaptureCommandStderr(
+    wrapper_utils.CommandToRun(args))
+
+  sys.stderr.write(stderr)
+  return returncode
+
+if __name__ == '__main__':
   sys.exit(main())