build: `cmake --install` fails if only select targets are built #31745

1. 
   fanquake commented at 10:22 AM on January 28, 2025: member

   Noticed this when going to update the lighting docs, porting what they do using Autotools. i.e:

   ./autogen.sh
   ./configure
   make src/bitcoind src/bitcoin-cli
   make install
   

   If you attempt the same with master:

   cmake -B build
   cmake --build build --target bitcoind bitcoin-cli
   cmake --install build
   -- Install configuration: "RelWithDebInfo"
   CMake Error at build/src/test/cmake_install.cmake:57 (file):
     file INSTALL cannot find "/root/ci_scratch/build/src/test/test_bitcoin": No
     such file or directory.
   Call Stack (most recent call first):
     build/src/cmake_install.cmake:77 (include)
     build/cmake_install.cmake:57 (include)
   

   The output of cmake --build build --target list_install_components just prints (if configured with the kernel):

   cmake --build build --target list_install_components 
   > Available install components are: "Kernel" "Unspecified"
   

   so it seems like component based install either isn't yet possible, or the names are not easily discoverable.

   Otherwise, I don't think we should fail to install because we can't find a binary the user didn't want.

2. fanquake added the label Build system on Jan 28, 2025
3. 
   theuni commented at 5:49 PM on January 28, 2025: member

   This is frustrating, but it seems to be how CMake works. cmake --install build doesn't force any builds, but make -C build install does.

   I think what you're really looking for is a way to only build/install certain binaries. For that, the workaround would be to name each one as a separate component. That would allow for:

   cmake -B build
   cmake --build build --target bitcoind bitcoin-cli
   cmake --install build --component bitcoind bitcoin-cli
   

4. 
   hebasto commented at 12:23 PM on January 29, 2025: member

   I think what you're really looking for is a way to only build/install certain binaries. For that, the workaround would be to name each one as a separate component. That would allow for:

   cmake -B build cmake --build build --target bitcoind bitcoin-cli cmake --install build --component bitcoind bitcoin-cli

   I agree. We have already done it for the bitcoinkernel target.

   On the other hand, the CMAKE_SKIP_INSTALL_ALL_DEPENDENCY variable seems not a proper solution because it affects the all target.

5. fanquake added this to the milestone 29.0 on Jan 31, 2025
6. fanquake closed this on Feb 14, 2025

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7. fanquake referenced this in commit 73e2ec1373 on Feb 14, 2025

Milestone
29.0