[cmake-developers] CMAKE_CURRENT_SOURCE_DIR points to build dir at build time

[Paul Cercueil]

Hi Brad,

On 15/05/2015 17:09, Brad King wrote:
> On 05/15/2015 05:09 AM, Paul Cercueil wrote:
>> set(CS_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/MyLib.cs
>>                  ${CMAKE_CURRENT_SOURCE_DIR}/AssemblyInfo.cs)
>> add_custom_command(OUTPUT mylib.dll
>>                  COMMAND mcs /target:library /out:mylib.dll /debug /keyfile:${CMAKE_CURRENT_SOURCE_DIR}/key.snk ${CS_SOURCES})
>>
>> Under Windows, it will generate fine but Visual Studio will fail to
>> build, stating that the "C:\build\Mylib.cs" and
>> "C:\build\AssemblyInfo.cs" files cannot be found (source dir is
>> "C:\src"). This indicates that it is in fact trying to find those files
>> in the build directory, instead of the source directory.
>
> CMake does not run during the build and there is no notion of
> evaluating CMake variables during the build.  The references
> in your example code will be expanded during configuration
> and the value should be generated into the .vcxproj file
> without any such variable reference.
>
> Take a look at the generated .vcxproj file.  How does the
> custom command appear there?
>
> -Brad
>

I understand that CMake doesn't run at build time, that was a bad choice 
of words.

In the generated .vcxproj I have something like that:

C:\Windows\Microsoft.NET\Framework\v4.0.30319\csc.exe /target:library 
/out:C:/build/mylib.dll /debug /keyfile:C:/src/key.snk C:/src/MyLib.cs 
C:/build/AssemblyInfo.cs

The paths look fine, yet Visual Studio complains that it can't find 
C:/build/MyLib.cs. But now I understand the reason, it's because of the 
path separator. If I use a backslash '\' then csc.exe suceeds. I guess 
the reason why it was looking for the source in C:\build is because 
that's the current directory.

Thanks!
-Paul