# What does /fast do on install targets?

**URL:** https://discourse.cmake.org/t/what-does-fast-do-on-install-targets/5397
**Category:** Usage
**Created:** [April 7, 2022, 1:15pm UTC](https://discourse.cmake.org/t/what-does-fast-do-on-install-targets/5397 "2022-04-07T13:15:59Z")
**Posts on this page:** 3
**Page:** 1

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### Author: ![mathomp4](https://discourse.cmake.org/user_avatar/discourse.cmake.org/mathomp4/32/176_2.png) [@mathomp4](https://discourse.cmake.org/u/mathomp4)
#### Post date: [April 7, 2022, 1:15pm UTC](https://discourse.cmake.org/t/what-does-fast-do-on-install-targets/5397/1 "2022-04-07T13:15:59Z")

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This is probably a FAQ, but I couldn’t find anything in the CMake docs or Google, so I thought I’d ask here.

I was doing some tab-completion today and saw that there is an `install/fast` target (and, of course, `install/strip/fast` and `install/local/fast`). Now I know what `install` and `install/strip` do and I _sort of_ understand what `install/local` does ([this thread](https://discourse.cmake.org/t/what-is-difference-between-install-install-local-and-install-strip/1329) kind of helped).

But I’m not sure what the `/fast` variants do. I tried to read the `Makefile` that CMake generated, but I couldn’t grok much from that. `install` and `install/fast` sort of seemed identical. I also tried looking at a `build.ninja` file but `install/fast` doesn’t seem to exist there!

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### Author: ![ben.boeckel](https://discourse.cmake.org/letter_avatar_proxy/v4/letter/b/ea5d25/32.png) [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [April 9, 2022, 12:50pm UTC](https://discourse.cmake.org/t/what-does-fast-do-on-install-targets/5397/2 "2022-04-09T12:50:19Z")

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The `/fast` variants are the same as the target without the `/fast` except that it has _no_ dependencies. It’s basically an “I know what I’m doing” kind of thing and failures due to missing (or out-of-date) dependencies are expected.

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### Author: ![mathomp4](https://discourse.cmake.org/user_avatar/discourse.cmake.org/mathomp4/32/176_2.png) [@mathomp4](https://discourse.cmake.org/u/mathomp4)
#### Post date: [April 9, 2022, 2:45pm UTC](https://discourse.cmake.org/t/what-does-fast-do-on-install-targets/5397/3 "2022-04-09T14:45:03Z")

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Ahhh. Interesting. Thanks!

I think I might have to try and shoot myself in the foot a few times now. 😃