[cmake-developers] [CMake 0016074]: Setting link_directories in toolchain file is only used for compiler tests, and inhibits effect of repeating the command

[Mantis Bug Tracker]

The following issue has been SUBMITTED. 
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https://cmake.org/Bug/view.php?id=16074 
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Reported By:                Antonio
Assigned To:                
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Project:                    CMake
Issue ID:                   16074
Category:                   (No Category)
Reproducibility:            have not tried
Severity:                   minor
Priority:                   normal
Status:                     new
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Date Submitted:             2016-04-21 09:58 EDT
Last Modified:              2016-04-21 09:58 EDT
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Summary:                    Setting link_directories in toolchain file is only
used for compiler tests, and inhibits effect of repeating the command
Description: 
In the attached example,
TOOLCHAIN FILE:
link_directories("D:/abcd")

CMAKELISTS.TXT:
project(dummyProject)
cmake_minimum_required(VERSION 3.4)
link_directories("D:/abcd")
link_directories("D:/efgh")
add_library(dummyTarget SHARED dummy.cpp)

At linking stage, only the "-LD:/efgh" will be there:
cmd.exe /C "cd . && <compiler> -shared -o libdummyTarget.dll
-Wl,--out-implib,libdummyTarget.dll.a
-Wl,--major-image-version,0,--minor-image-version,0
CMakeFiles/dummyTarget.dir/dummy.cpp.obj -LD:/efgh -lkernel32 -luser32 -lgdi32
-lwinspool -lshell32 -lole32 -loleaut32 -luuid -lcomdlg32 -ladvapi32 && cd ."

Note: In the CMakeOutput.log file is possible to see that -LD:/abcd is used in
the preliminary compiler tests.

Use case:
I am dealing with a toolchain where the std library is in a specific location,
and to pass the preliminary cmake compiler tests I must set the std library
location with a link_directories command. Since it is toolchain specific, it
makes sense to set in the toolchain file. I can pass the compiler tests if I
call `link_directories` in the toolchain file.

The only workaround I could find so far was to directly set the flag (still in
the toolchain file):

# SET(CMAKE_EXE_LINKER_FLAGS "-LD:/abcd")
# SET(CMAKE_SHARED_LINKER_FLAGS "-LD:/abcd")
# SET(CMAKE_MODULE_LINKER_FLAGS "-LD:/abcd")

Steps to Reproduce: 
1) Take the project in attachment
2) Configure with the attached toolchain, for example using ninja generator
3a) With ninja, run ninja -v to see the command line
3b) With make, run make.exe VERBOSE=1 to see the command line
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Issue History 
Date Modified    Username       Field                    Change               
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2016-04-21 09:58 Antonio        New Issue                                    
2016-04-21 09:58 Antonio        File Added: CMakeBugProject.zip                 
  
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