[CMake] Reverse dependencies (Unix Makefiles)

[Jesper Eskilson]

On 05/25/2010 05:35 PM, Michael Hertling wrote:
> On 05/25/2010 03:58 PM, Jesper Eskilson wrote:
>> On 05/25/2010 02:41 PM, Michael Hertling wrote:
>>
>>> Exactly: The need for A's repetition in the link line is a sole affair
>>> of A and C. Therefore, IMO, it should not be brought explicitly to D's
>>> link line whereas an approach with two TARGET_LINK_LIBRARIES() for the
>>> A'n'C circular dependency and one for D against A would express the
>>> actual relations quite accurately.
>>
>> Can CMake express this for IMPORTED libraries as well. Both A, B, and C
>> in this case are (or can be) IMPORTED libraries, and
>> TARGET_LINK_LIBRARIES() fail if the first argument is an IMPORTED library.
>>
>> Until I can figure out how to do that, I'll have to go with repeating A
>> on D's link line.
>
> Look at the following CMakeLists.txt:
>
> CMAKE_MINIMUM_REQUIRED(VERSION 2.8 FATAL_ERROR)
> PROJECT(ICD C)
> # Generate circular dependent static libraries:
> FILE(WRITE A.c "void fA(void){ fC(); } void ident(void){}")
> FILE(WRITE C.c "void fC(void){ ident(); }")
> ADD_LIBRARY(A0 STATIC EXCLUDE_FROM_ALL A.c)
> ADD_LIBRARY(C0 STATIC EXCLUDE_FROM_ALL C.c)
> SET_TARGET_PROPERTIES(A0 PROPERTIES ARCHIVE_OUTPUT_NAME A)
> SET_TARGET_PROPERTIES(C0 PROPERTIES ARCHIVE_OUTPUT_NAME C)
> # Incorporate them as imported targets:
> ADD_LIBRARY(A STATIC IMPORTED)
> ADD_LIBRARY(C STATIC IMPORTED)
> SET_TARGET_PROPERTIES(A PROPERTIES IMPORTED_LOCATION
> ${CMAKE_CURRENT_BINARY_DIR}/libA.a)
> SET_TARGET_PROPERTIES(C PROPERTIES IMPORTED_LOCATION
> ${CMAKE_CURRENT_BINARY_DIR}/libC.a)
> # Declare their circular dependency:
> SET_TARGET_PROPERTIES(A PROPERTIES IMPORTED_LINK_INTERFACE_LIBRARIES C)
> SET_TARGET_PROPERTIES(C PROPERTIES IMPORTED_LINK_INTERFACE_LIBRARIES A)
> # Executable D linking against library A:
> FILE(WRITE D.c "void main(void){ fA(); }")
> ADD_EXECUTABLE(D D.c)
> TARGET_LINK_LIBRARIES(D A)
>
> After CMaking, type "make A0 C0" to build the circular dependent
> libA.a and libC.a, and then "make VERBOSE=1"; the link line is:
>
> gcc CMakeFiles/D.dir/D.c.o -o D -rdynamic libA.a libC.a libA.a libC.a
>
> The target property IMPORTED_LINK_INTERFACE_LIBRARIES seems to make it.

Will this still work with an executable E wich depends on B -> C -> B. 
Won't C pull in A as well?

--
/Jesper