The GoLang release (1.10) made the following announcement:
Go 1.10 is the last release that will run on OpenBSD 6.0. Go 1.11 will require OpenBSD 6.2.
Go 1.10 is the last release that will run on OS X 10.8 Mountain Lion or OS X 10.9 Mavericks. Go 1.11 will require OS X 10.10 Yosemite or later.
Go 1.10 is the last release that will run on Windows XP or Windows Vista. Go 1.11 will require Windows 7 or later.
While this requires no immediate action for anyone, we would like the users of the CF CLI to be aware that once the CF CLI upgrades to GoLang 1.11, it will no longer support operating systems that GoLang does not support.
Following the GoLang release schedule, Go 1.11 will be released around August 2018, giving affected customers at least six more months to upgrade to a supported version.
If you feel like the CF CLI Team should refrain from upgrading to GoLang 1.11 upon its release, please voice your concerns now and we will adjust our upgrade cycle accordingly.
According to our downloads stats of the last year, Windows makes up 5.54% and OS X makes up 1.98% of totals downloads.
Approximately 0.1% of total CF CLI downloads over the last year are made by the affected systems. The overwhelming majority of said downloads are Windows XP.
Microsoft dropped support of Windows XP on April 8, 2014.
Microsoft dropped support of Vista on April 11, 2017.
According to the Apple Security Updates page, the last time Mavericks (10.9) was updated was in March 2017. It has not gotten any security fixes since then.