cmake install_error ai_generated true

CMake Error: install(EXPORT) generated target "mylib" but target "mylib" has library output path "/build/lib" that does not match the install destination "/usr/local/lib"

ID: cmake/export-library-path-mismatch

Also available as: JSON · Markdown · 中文

85%Fix Rate

90%Confidence

1Evidence

2024-03-22First Seen

Version Compatibility

Version	Status	Introduced	Deprecated	Notes
cmake 3.26.0	active	—	—	—
cmake 3.27.0	active	—	—	—
cmake 3.28.0	active	—	—	—

Root Cause

The target's LIBRARY_OUTPUT_DIRECTORY or ARCHIVE_OUTPUT_DIRECTORY differs from the DESTINATION specified in install(TARGETS), causing CMake to detect a mismatch during export generation.

generic

中文

目标的 LIBRARY_OUTPUT_DIRECTORY 或 ARCHIVE_OUTPUT_DIRECTORY 与 install(TARGETS) 中指定的 DESTINATION 不同，导致 CMake 在生成导出时检测到不匹配。

Official Documentation

https://cmake.org/cmake/help/latest/command/install.html#exporting-targets

Workarounds

90% success Set the target's output directory to match the install destination using generator expressions: set_target_properties(mylib PROPERTIES LIBRARY_OUTPUT_DIRECTORY "${CMAKE_INSTALL_PREFIX}/lib" ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_INSTALL_PREFIX}/lib" ) Then ensure install(TARGETS mylib DESTINATION lib) matches.
```
Set the target's output directory to match the install destination using generator expressions:

set_target_properties(mylib PROPERTIES
  LIBRARY_OUTPUT_DIRECTORY "${CMAKE_INSTALL_PREFIX}/lib"
  ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_INSTALL_PREFIX}/lib"
)

Then ensure install(TARGETS mylib DESTINATION lib) matches.
```
85% success Use a relative path in install(DESTINATION) that matches the build output: set_target_properties(mylib PROPERTIES LIBRARY_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/lib") install(TARGETS mylib DESTINATION "${CMAKE_BINARY_DIR}/lib") Then generate the export with install(EXPORT ... DESTINATION "${CMAKE_BINARY_DIR}/lib")
```
Use a relative path in install(DESTINATION) that matches the build output:

set_target_properties(mylib PROPERTIES LIBRARY_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/lib")
install(TARGETS mylib DESTINATION "${CMAKE_BINARY_DIR}/lib")

Then generate the export with install(EXPORT ... DESTINATION "${CMAKE_BINARY_DIR}/lib")
```

中文步骤

使用生成器表达式将目标的输出目录设置为与安装目标匹配：

set_target_properties(mylib PROPERTIES
  LIBRARY_OUTPUT_DIRECTORY "${CMAKE_INSTALL_PREFIX}/lib"
  ARCHIVE_OUTPUT_DIRECTORY "${CMAKE_INSTALL_PREFIX}/lib"
)

然后确保 install(TARGETS mylib DESTINATION lib) 匹配。

使用与构建输出匹配的 install(DESTINATION) 相对路径：

set_target_properties(mylib PROPERTIES LIBRARY_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/lib")
install(TARGETS mylib DESTINATION "${CMAKE_BINARY_DIR}/lib")

然后使用 install(EXPORT ... DESTINATION "${CMAKE_BINARY_DIR}/lib") 生成导出。

Dead Ends

Common approaches that don't work:

Change LIBRARY_OUTPUT_DIRECTORY to match the install destination 60% fail
LIBRARY_OUTPUT_DIRECTORY affects build-time output, not install; changing it may break build scripts or tests that expect the library in the original build directory.
Remove install(EXPORT) entirely 90% fail
Removes the export mechanism, so downstream projects using find_package will fail to locate the package.