Sync with maint

diff --git a/ci/lib.sh b/ci/lib.sh
index fd799ae66311d62d2eb62b7fe5aaf23171312d15..44db2d5cbb2241c7bd3ffd69d15a73c1fd4357ae 100755 (executable)
--- a/ci/lib.sh
+++ b/ci/lib.sh
@@ -163,8 +163,10 @@ linux-clang|linux-gcc)
        export GIT_TEST_HTTPD=YesPlease
 
        # The Linux build installs the defined dependency versions below.
-       # The OS X build installs the latest available versions. Keep that
-       # in mind when you encounter a broken OS X build!
+       # The OS X build installs much more recent versions, whichever
+       # were recorded in the Homebrew database upon creating the OS X
+       # image.
+       # Keep that in mind when you encounter a broken OS X build!
        export LINUX_P4_VERSION="16.2"
        export LINUX_GIT_LFS_VERSION="1.5.2"