[cmake-developers] CMAKE_SHARED_LIBRARY_LINK_${lang}_FLAGS and CMP0065

[Stephen Kelly]

Brad King wrote:

>>>> out of place in cmLocalGenerator. If it were returned from
>>>> cli.GetItems,
>>>
>>> Yes, it could be moved.
>> 
>> Ok. I might look into that.
> 
> It looks like OutputLinkLibraries currently puts the flag in the
> linkLibs (which goes to the <LINK_LIBRARIES> placeholder) but it
> would more sensibly be located in the linkFlags (which goes to
> the <LINK_FLAGS> placeholder).  If we do clean this up it should
> be moved to <LINK_FLAGS>.  Therefore it should not go in GetItems,
> but instead in a separate helper that all generators can share.

Do you know what CMAKE_EXE_EXPORTS_${lang}_FLAG is? It is added to the 
linkFlags already for executables with exports.

For Linux, it contains 

 "-Wl,--export-dynamic"

CMAKE_SHARED_LIBRARY_LINK_${lang}_FLAGS contains

 "-rdynamic"

for Linux-GNU.

According to 

 https://gcc.gnu.org/onlinedocs/gcc/Link-Options.html

rdynamic means:

 "Pass the flag -export-dynamic to the ELF linker, on targets that support 
it."

Is CMP0065 adding redundant flags?

Thanks,

Steve.