[CMake] cmake side effects: possible bug

[Brad King]

Michael Bell wrote:
> Ok, it certainly makes sense that running cmake globally would
> simplify things, which is a good thing. It does seem to cause a
> problem for me that maybe you can help me work around:
> 
> Say I have a several subdirectories, each with C++ code and perl
> wrappers to that code. If I change the code in one directory and run
> make, it compiles the code, then ALL perl files are copied, but only
> the files from the current directory are made executable. So, while I
> had executable perl wrappers before, they are no longer executable
> except from the one directory.
> 
> The solution I have adopted for now is to run make from the root,
> which copies and makes all scripts executable. But, that means C++
> code must be compiled in every directory too, even if I don't want
> that to happen. Or, perl scripts get copied that I don't want copied
> yet. In other words, I need a way for make to act locally.
> 
> Note that I am running cmake only once, before any of the above.
> Everything I wrote about happens when I run make.

The new "global" execution means things are now target oriented instead
of directory oriented.  This is consistent with how things have always
worked on the Visual Studio generators.

You should convert your view to be target based also and things will
make much more sense.  You could move the copy/set-exec to a custom
target with a custom command and then make other targets depend on it.

ADD_CUSTOM_COMMAND(
  OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/myscript1.pl
  COMMAND ${CMAKE_COMMAND} -E copy
${CMAKE_CURRENT_SOURCE_DIR}/myscript1.pl.in
${CMAKE_CURRENT_BINARY_DIR}/myscript1.pl
  COMMAND chmod 755 ${CMAKE_CURRENT_BINARY_DIR}/myscript1.pl
  DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/myscript1.pl.in
  )
ADD_CUSTOM_COMMAND(
  OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/myscript2.pl
  COMMAND ${CMAKE_COMMAND} -E copy
${CMAKE_CURRENT_SOURCE_DIR}/myscript2.pl.in
${CMAKE_CURRENT_BINARY_DIR}/myscript2.pl
  COMMAND chmod 755 ${CMAKE_CURRENT_BINARY_DIR}/myscript2.pl
  DEPENDS ${CMAKE_CURRENT_SOURCE_DIR}/myscript2.pl.in
  )
ADD_CUSTOM_TARGET(prepare_myscripts DEPENDS
${CMAKE_CURRENT_BINARY_DIR}/myscript1.pl
${CMAKE_CURRENT_BINARY_DIR}/myscript2.pl)

Now for any target whose build requires the scripts do:
ADD_DEPENDENCY(some_target prepare_myscripts)

-Brad