# Changing target output path based on architecture

**URL:** https://discourse.cmake.org/t/changing-target-output-path-based-on-architecture/8839
**Category:** Code
**Tags:** os:windows, comp:msvc, gen:vs
**Created:** [August 29, 2023, 7:14pm UTC](https://discourse.cmake.org/t/changing-target-output-path-based-on-architecture/8839 "2023-08-29T19:14:03Z")
**Posts on this page:** 4
**Page:** 1

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### Author: ![Saviz](https://discourse.cmake.org/user_avatar/discourse.cmake.org/saviz/32/6194_2.png) [@Saviz](https://discourse.cmake.org/u/Saviz)
#### Post date: [August 29, 2023, 7:14pm UTC](https://discourse.cmake.org/t/changing-target-output-path-based-on-architecture/8839/1 "2023-08-29T19:14:03Z")

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Sometimes, I might need to modify the **output directory** based on **whether my build is 32-bit or 64-bit**. Currently, this is what I have in place:

```auto
# Decide where to put the target based on the architecture (32/64 bit)

if(CMAKE_SIZEOF_VOID_P EQUAL 8) # If it is 64-bit...

	set(OUTPUT_DIRECTORY "${CMAKE_SOURCE_DIR}/../build/bin/${CMAKE_SYSTEM_NAME}/64-bit/")

endif()

if(CMAKE_SIZEOF_VOID_P EQUAL 4) # If it is 32-bit...

	set(OUTPUT_DIRECTORY "${CMAKE_SOURCE_DIR}/../build/bin/${CMAKE_SYSTEM_NAME}/32-bit/")

endif()

```

  

I then use this path for the targets using the following approach:

```auto
set(CMAKE_RUNTIME_OUTPUT_DIRECTORY "${OUTPUT_DIRECTORY}/exe/$<CONFIG>")
set(CMAKE_LIBRARY_OUTPUT_DIRECTORY "${OUTPUT_DIRECTORY}/lib_dynamic/$<CONFIG>")
set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY "${OUTPUT_DIRECTORY}/lib_static/$<CONFIG>")

```

  

For the time being, this approach works just fine. Nonetheless, I’m curious if there is a better method to approach the problem **since not every system out there would necessarily be 32 or 64 bit**. In addition, as I am not experienced with CMake, there might be more problems to this method that I may not be able to spot at the current time.

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<div class="post-metadata">

### 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: [August 30, 2023, 12:02pm UTC](https://discourse.cmake.org/t/changing-target-output-path-based-on-architecture/8839/2 "2023-08-30T12:02:12Z")

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You may want to include `${CMAKE_ARCHITECTURE}` in there as there are other processors out there. Note that this does not work for universal binaries on macOS where one artifact has code for multiple architectures. Also note that `CMAKE_SIZEOF_VOID_P` is _now_ consistent for universal builds, but was not when 32 and 64 bit Intel architectures co-existed in them.

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<div class="post-metadata">

### Author: ![Saviz](https://discourse.cmake.org/user_avatar/discourse.cmake.org/saviz/32/6194_2.png) [@Saviz](https://discourse.cmake.org/u/Saviz)
#### Post date: [August 30, 2023, 11:35pm UTC](https://discourse.cmake.org/t/changing-target-output-path-based-on-architecture/8839/3 "2023-08-30T23:35:44Z")

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I must admit that I am feeling a little confused. Does the code provided below align with your intended meaning?

  

```auto
# Replacing the hardcoded architecture (32-bit/64-bit) with "${CMAKE_ARCHITECTURE}".

set(OUTPUT_DIRECTORY "${CMAKE_SOURCE_DIR}/../build/bin/${CMAKE_SYSTEM_NAME}/${CMAKE_ARCHITECTURE}/")

```

  

If that’s the case, considering that ${CMAKE\_ARCHITECTURE} may lead to inaccuracies under macOS, what would be the solution for that platform?

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<div class="post-metadata">

### 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: [August 30, 2023, 11:41pm UTC](https://discourse.cmake.org/t/changing-target-output-path-based-on-architecture/8839/4 "2023-08-30T23:41:41Z")

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That would help if you want to overlay things with different architectures, yes. For macOS with universal binaries, I’d just use the “architecture” `universal2`.