[CMake] compiler flag property overwriting parents' settings in VS 2010

[Shiqing Fan]

  Hi,

With CMake 2.8.2 and Visual Studio 2010, it seems that using compiler 
flag property in set_source_files_properties will overwrite the 
inherited properties in some cases.

For example, in one cmake project, we have a global setting of include 
headers:

     include_headers(${global_include_path})

for some of the source files in this project, we have:

     set_source_files_properties(source1.c PROPERTIES COMPILE_FLAGS 
"/I${local_include_path}")

with this settings, we want source1.c have both ${global_include_path} 
and ${local_include_path} included, this is only possible with Visual 
Studio 2008, but not Visual Studio 2010, ${global_include_path} is not 
inherited for source1.c, I have to manually change the property of 
source1.c in VS 2010.

It says in CMake document, for set_source_files_properties command : 
"COMPILE_FLAGS (string) is passed to the compiler as additional command 
line arguments when the source file is compiled. " But it's not true for 
me in Visual Studio 2010. The "additional command line arguments" is 
overwriting the inherited ones.

I don't know if this has been posted or not, I didn't find any solution 
for this. Does any one know how can I solve this problem? Thanks a lot.


Shiqing