old_contents: """Macros for building Objective-C libraries with strict warnings."""
  
  # This list is derived from
  # http://programmers.stackexchange.com/questions/122608/clang-warning-flags-for-objective-c-development
  # with a few turned off because the warning code is widely present in Material
  # Components and seems innocuous.
  COMMON_COPTS = [
      "-Wall",  # Standard known-to-be-bugs warnings.
      "-Wcast-align",  # Casting a pointer such that alignment is broken.
      "-Wconversion",  # Numeric conversion warnings.
      "-Wdocumentation",  # Documentation checks.
      "-Werror",  # All warnings as errors.
      "-Wextra",  # Many useful extra warnings.
      "-Wdocumentation",  # Warn when documentation is out of date.
      "-Wimplicit-atomic-properties",  # Dynamic properties should be non-atomic.
      "-Wmissing-prototypes",  # Global function is defined without a previous prototype.
      "-Wnewline-eof",  # No newline at the end of the file.
      "-Wno-error=deprecated",  # Deprecation warnings are never errors.
      "-Wno-error=deprecated-implementations",  # Deprecation warnings are never errors.
      "-Wno-sign-conversion",  # Do not warn on sign conversions.
      "-Wno-unused-parameter",  # Do not warn on unused parameters.
      "-Woverlength-strings",  # Strings longer than the C maximum.
      "-Wshadow",  # Local variable shadows another variable, parameter, etc.
      "-Wstrict-selector-match",  # Compiler can't figure out the right selector.
      "-Wundeclared-selector",  # Compiler doesn't see a selector.
      "-Wunreachable-code",  # Code will never be reached.
  ]
  
  def strict_warnings_objc_library(
      name,
      copts = [],
      **kwargs):
    """Declare an Objective-C library with strict warning flags."""
    native.objc_library(
        name = name,
        copts = copts + COMMON_COPTS,
        **kwargs)
  
new_contents: """Macros for building Objective-C libraries with strict warnings."""
  
  # This list is derived from
  # http://programmers.stackexchange.com/questions/122608/clang-warning-flags-for-objective-c-development
  # with a few turned off because the warning code is widely present in Material
  # Components and seems innocuous.
  COMMON_COPTS = [
      "-Wall",  # Standard known-to-be-bugs warnings.
      "-Wcast-align",  # Casting a pointer such that alignment is broken.
      "-Wconversion",  # Numeric conversion warnings.
      "-Wdocumentation",  # Documentation checks.
      "-Werror",  # All warnings as errors.
      "-Wextra",  # Many useful extra warnings.
      "-Wdocumentation",  # Warn when documentation is out of date.
      "-Wimplicit-atomic-properties",  # Dynamic properties should be non-atomic.
      "-Wmissing-prototypes",  # Global function is defined without a previous prototype.
      "-Wnewline-eof",  # No newline at the end of the file.
      "-Wno-error=deprecated",  # Deprecation warnings are never errors.
      "-Wno-error=deprecated-implementations",  # Deprecation warnings are never errors.
      "-Wno-partial-availability",
      "-Wno-sign-conversion",  # Do not warn on sign conversions.
      "-Wno-unused-parameter",  # Do not warn on unused parameters.
      "-Woverlength-strings",  # Strings longer than the C maximum.
      "-Wshadow",  # Local variable shadows another variable, parameter, etc.
      "-Wstrict-selector-match",  # Compiler can't figure out the right selector.
      "-Wstrict-prototypes",
      "-Wundeclared-selector",  # Compiler doesn't see a selector.
      "-Wunreachable-code",  # Code will never be reached.
      "-Wunused-comparison",
      "-Wunused-const-variable",
      "-Wunused-exception-parameter",
      "-Wunused-function",
      "-Wunused-label",
      "-Wunused-member-function",
      "-Wunused-private-field",
      "-Wunused-property-ivar",
      "-Wunused-result",
      "-Wunused-value",
      "-Wunused-variable",
      "-Wunused-volatile-lvalue",
      "-Wused-but-marked-unused",
  ]
  
  def strict_warnings_objc_library(
      name,
      copts = [],
      **kwargs):
    """Declare an Objective-C library with strict warning flags."""
    native.objc_library(
        name = name,
        copts = copts + COMMON_COPTS,
        **kwargs)
  
subject: Update warnings to match the MDC iOS project (#2)