[CMake] errors with add_custom_command and add_custom_target

[Vania Joloboff]

Hi

I have a generator that generates some, but not all of the source files.
My understanding was that I should use add_custom_command for that

When I do
set(EXIST_SOURCES A.cc B.cc C.cc)
set(GEN_SOURCES X.cc Y.cc Z.cc)
add_custom_command(OUTPUT ${GEN_SOURCES}
                        COMMAND generator
                        MAIN_DEPENDENCY gendir/generator   )
set_property(SOURCE ${GEN_SOURCES} PROPERTY GENERATED )
add_library(mylib OBJECT "${EXIST_SOURCES} ${GEN_SOURCES}" )

I get error "Cannot find source file : X.cc"

So, I tried

set(EXIST_SOURCES A.cc B.cc C.cc)
set(GEN_SOURCES X.cc Y.cc Z.cc)
add_custom_target(generate
               COMMAND generator
               COMMENT "Generate"
               DEPENDS gendir/generator   )
set_property(SOURCE ${GEN_SOURCES} PROPERTY GENERATED )
add_library(mylib OBJECT "${EXIST_SOURCES} ${GEN_SOURCES}" )
add_dependencies(mylib generate)

I get same error "Cannot find source file : X.cc"

I just don't get it...

Vania