Sometimes[1] CMake will do a build on Darwin without setting up CMAKE_OSX_SYSROOT. This appears to be to support the "basic POSIX-only case"[2]. The hard-coded CMake logic we're mimicking[3] handles this case, so do the same. [1]kris/onging/CECPQ3_patch15f6b93fbf3a/Modules/Platform/Darwin-Initialize.cmake (L48)
[2]43b74793de
[3] https://github.com/Kitware/CMake/blob/master/Source/cmLocalGenerator.cxx#L1307 Change-Id: Ica5ae8510d07eca384cc366dd3de10b0c1ce0f81 Reviewed-on: https://boringssl-review.googlesource.com/16245 Commit-Queue: David Benjamin <davidben@google.com> Commit-Queue: Adam Langley <agl@google.com> Reviewed-by: Adam Langley <agl@google.com> CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>