# Combining two projects
**URL:** https://discourse.cmake.org/t/combining-two-projects/5988
**Category:** Usage
**Tags:** os:linux, comp:gcc
**Created:** [July 4, 2022, 7:07am UTC](https://discourse.cmake.org/t/combining-two-projects/5988 "2022-07-04T07:07:12Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@alexanderzhirov](https://discourse.cmake.org/u/alexanderzhirov)
#### Post date: [July 4, 2022, 7:07am UTC](https://discourse.cmake.org/t/combining-two-projects/5988/1 "2022-07-04T07:07:12Z")
There are two projects: [`FreeRDP`](https://github.com/FreeRDP/FreeRDP) and [`cFLTK`](https://github.com/MoAlyousef/cfltk) (a `C` wrapper for the `FLTK` library).
I am writing a GUI for `FreeRDP` and I want to combine my work with the `FreeRDP` source code project.
My attempt at unification:
I have separately compiled a static library from the `cFLTK` source code. Next, I placed my developments in a separate directory. Created an assembly file there `CMakeLists.txt`. My source code is also compiled as a static library.
Further in the file `CMakeLists.txt` I am connecting my developments to the `FreeRDP` project.
```cmake
...
set(GFREE gfree)
add_subdirectory(${GFREE})
set(GFREE_FLAGS
gfree
cfltk
fltk
fltk_images
fltk_jpeg
fltk_z
png16
m
X11
Xinerama
Xfixes
Xcursor
Xft
Xrender
fontconfig
)
ADD_LIBRARY(cfltk STATIC IMPORTED)
set_target_properties(cfltk PROPERTIES IMPORTED_LOCATION ${CMAKE_CURRENT_SOURCE_DIR}/gfree_lib/libcfltk.a)
ADD_LIBRARY(fltk STATIC IMPORTED)
set_target_properties(fltk PROPERTIES IMPORTED_LOCATION ${CMAKE_CURRENT_SOURCE_DIR}/gfree_lib/libfltk.a)
ADD_LIBRARY(fltk_images STATIC IMPORTED)
set_target_properties(fltk_images PROPERTIES IMPORTED_LOCATION ${CMAKE_CURRENT_SOURCE_DIR}/gfree_lib/libfltk_images.a)
ADD_LIBRARY(fltk_jpeg STATIC IMPORTED)
set_target_properties(fltk_jpeg PROPERTIES IMPORTED_LOCATION ${CMAKE_CURRENT_SOURCE_DIR}/gfree_lib/libfltk_jpeg.a)
ADD_LIBRARY(fltk_z STATIC IMPORTED)
set_target_properties(fltk_z PROPERTIES IMPORTED_LOCATION ${CMAKE_CURRENT_SOURCE_DIR}/gfree_lib/libfltk_z.a)
....
set(${MODULE_PREFIX}_LIBS ${${MODULE_PREFIX}_LIBS} freerdp-client freerdp m ${GFREE_FLAGS})
....
```
Everything is assembled without errors and runs.
At first, the GUI I wrote is called, when using which I then call the `FreeRDP` connection.
The problem is that when I connect, I get errors.
```nohighlight
[21:01:24:425] [4624:4625] [ERROR][com.freerdp.core.nego] - Protocol Security Negotiation Failure
[21:01:24:426] [4624:4625] [ERROR][com.freerdp.core] - rdp_client_connect:freerdp_set_last_error_ex ERRCONNECT_SECURITY_NEGO_CONNECT_FAILED [0x0002000C]
[21:01:24:426] [4624:4625] [ERROR][com.freerdp.core.connection] - Error: protocol security negotiation or connection failure
```
I tried to build `FreeRDP` without my own developments - the connection is made without problems.
I suspect that combining my code and the `FreeRDP` code leads to some problems.
Perhaps I am not combining these projects correctly.
Is it possible to properly combine two `CMake` projects in order not to radically edit other people’s configs? I ask you to help me understand and suggest in this matter. Thank you in advance!
---
### Author:  [@ben.boeckel](https://discourse.cmake.org/u/ben.boeckel)
#### Post date: [July 9, 2022, 1:10pm UTC](https://discourse.cmake.org/t/combining-two-projects/5988/2 "2022-07-09T13:10:37Z")
It certainly could be that your combination misses some detail (say an optional dependency?), but that is outside the scope of here. Maybe the FreeRDP developers would have a better inkling of where to start looking?
> [@alexanderzhirov](#):
>
> Is it possible to properly combine two `CMake` projects in order not to radically edit other people’s configs?
In general, no. Well-behaved projects are probably easier to do this with (e.g., those that namespace all variables and internal APIs).