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cmakeninja

CMake setting to Ninja rebuild when header change?

Apparently, Ninja has to be configured to treat headers as dependencies: https://ninja-build.org/manual.html#ref_headers.

How do I tell CMake to generate this into my build.ninja?

Solution

  • If I look into my build.ninja files generated with CMake for e.g. GCC I do have the necessary dependency file entries automatically generated (see DEP_FILE):

    #=============================================================================
# Object build statements for EXECUTABLE target MyExe

build CMakeFiles/MyExe.dir/foo.cc.obj: CXX_COMPILER ../foo.cc
  DEP_FILE = CMakeFiles/MyExe.dir/foo.cc.obj.d
  FLAGS = -fdiagnostics-color=always -Wconversion
  OBJECT_DIR = CMakeFiles\MyExe.dir
  OBJECT_FILE_DIR = CMakeFiles\MyExe.dir

    And the dependency checking works as expected. Just touch or change one of the header dependencies and ninja will automatically rebuild the necessary sources.