message: removing asan 64 for osx images with xcode older than 10 - see this build:
diff: @@ -176,22 +176,22 @@ matrix:
  sources: *apt_sources
  # Xcode 8 Clang
  - - env: COMPILER=clang++ HAS_ASAN_32=true HAS_ASAN_64=true
  + - env: COMPILER=clang++ HAS_ASAN_32=true # no HAS_ASAN_64 - errors since using thread_local even in single-threaded cases
  osx_image: xcode8
  os: osx
  # Xcode 8.3 Clang
  - - env: COMPILER=clang++ HAS_ASAN_32=true HAS_UBSAN_32=true HAS_ASAN_64=true HAS_UBSAN_64=true
  + - env: COMPILER=clang++ HAS_ASAN_32=true HAS_UBSAN_32=true HAS_UBSAN_64=true # no HAS_ASAN_64 - errors since using thread_local even in single-threaded cases
  osx_image: xcode8.3
  os: osx
  # Xcode 9.2 Clang
  - - env: COMPILER=clang++ HAS_ASAN_32=true HAS_UBSAN_32=true HAS_ASAN_64=true HAS_UBSAN_64=true
  + - env: COMPILER=clang++ HAS_ASAN_32=true HAS_UBSAN_32=true HAS_UBSAN_64=true # no HAS_ASAN_64 - errors since using thread_local even in single-threaded cases
  osx_image: xcode9.2
  os: osx
  # Xcode 9.4 Clang
  - - env: COMPILER=clang++ HAS_ASAN_32=true HAS_UBSAN_32=true HAS_ASAN_64=true HAS_UBSAN_64=true
  + - env: COMPILER=clang++ HAS_ASAN_32=true HAS_UBSAN_32=true HAS_UBSAN_64=true # no HAS_ASAN_64 - errors since using thread_local even in single-threaded cases
  osx_image: xcode9.4
  os: osx
  @@ -233,6 +233,7 @@ matrix:
  # OSX LLVM-GCC
  - env: COMPILER=g++ HAS_ASAN_32=true HAS_ASAN_64=true
  compiler: gcc
  + osx_image: xcode10
  os: osx
  allow_failures:
  