Hi,
I have a project in a directory where two directory components are symbolic links (to directories). Normally I’m use to see CMAKE_* paths to be “logical” (i.e. what “pwd -L” shows). However, under circumstances some symlinks are resolved, sometimes even all, so that some CMAKE_* paths are “physical” (i.e. what “pwd -P” shows).
Under what circumstances CMAKE_CURRENT_BINARY_DIR and CMAKE_SOURCE_DIR do resolve symbolic links?
In my current situation I see that CMAKE_SOURCE_DIR is logical, as expected, but CMAKE_CURRENT_BINARY_DIR is neither logical nor physical but “mixed”: the last symlink is resolved, but not all. I tried to make a minimal example but there both got “mixed”. When I specify a path component too much plus extra “…” (resulting in the same) in cmake argument, then I see CMAKE_SOURCE_DIR logical and CMAKE_CURRENT_BINARY_DIR “mixed”. This is not exactly my sitation but I don’t understand it either.
When are symlinks resolved? How to use “logical” paths everywhere?
Let me show an example.
sdettmer@farm21-1:/tmp/cmake-test/symlink-test $ find /tmp/project_root*|xargs ls -ld
lrwx... /tmp/project_root -> project_root.physical
drwx... /tmp/project_root.physical
lrwx... /tmp/project_root.physical/app1 -> application1.physical
drwx... /tmp/project_root.physical/application1.physical
drwx... /tmp/project_root.physical/application1.physical/build
drwx... /tmp/project_root.physical/application1.physical/prj
-rw-... /tmp/project_root.physical/application1.physical/prj/CMakeLists.txt
CMakeLists.txt
cmake_minimum_required(VERSION 3.6.2)
project(PRJ1)
message(STATUS "CMAKE_SOURCE_DIR=${CMAKE_SOURCE_DIR}")
message(STATUS "CMAKE_CURRENT_BINARY_DIR=${CMAKE_CURRENT_BINARY_DIR}")
now some invocations:
sdettmer@farm21-1:/tmp/project_root/app1/build $ rm -rf * ; cmake ../prj/
-- CMAKE_SOURCE_DIR=/tmp/project_root/application1.physical/prj
-- CMAKE_CURRENT_BINARY_DIR=/tmp/project_root/application1.physical/build
# both "mixed" (project root is not resolved, but app1 is resolved)
sdettmer@farm21-1:/tmp/project_root/app1/build $ rm -rf * ; cmake ../../app1/prj/
-- CMAKE_SOURCE_DIR=/tmp/project_root/app1/prj
-- CMAKE_CURRENT_BINARY_DIR=/tmp/project_root/application1.physical/build
# SOURCE is "logical" as expected, BINARY is "mixed" (only app1 is resolved)
sdettmer@farm21-1:/tmp/project_root/app1/build $ rm -rf * ; cmake /tmp/project_root/app1/prj
-- CMAKE_SOURCE_DIR=/tmp/project_root/app1/prj
-- CMAKE_CURRENT_BINARY_DIR=/tmp/project_root/application1.physical/build
# same: SOURCE is "logical" as expected, BINARY is "mixed" (only app1 is resolved)
I would like to have:
-- CMAKE_SOURCE_DIR=/tmp/project_root/app1/prj
-- CMAKE_CURRENT_BINARY_DIR=/tmp/project_root/app1/build
When does CMAKE_CURRENT_BINARY_DIR resolve symlinks in which parts of the path? How to avoid this?
Background is that I have generated header files in ${CMAKE_CURRENT_BINARY_DIR}/libaryX/include/ = /tmp/project_root/app1/build and I’m using ccache with CCACHE_WORKDIR=/tmp/project_root/app1 - which requires BINARY to be below SOURCE. The paths in real project are more complicated, here it is just to illustrate my question.
Any ideas?
cmake version 3.6.2
g++ 4.4.3 and newer
I cannot upload as attachment since I’m a new user, so I try uuencoded 
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====
EDIT: Attached cmake-symlink-test.tgz
Steffen