Use linker scripts instead of symlink.

[diptorupd]

WIP non-functional implementation for linker scripts instead of symlinks. Needs more fixes, cleans up and checks for OS.

[oleksandr-pavlyk]

Linker scripts can not self-reference. Python is not able to deal with chained linker scripts (.so referring to so.1 which refers to so.1.0).

This restricts us to use SOVERSION property to be the same as VERSION property.

With these changes:

diff --git a/dpctl-capi/CMakeLists.txt b/dpctl-capi/CMakeLists.txt
index bca778c..ca35369 100644
--- a/dpctl-capi/CMakeLists.txt
+++ b/dpctl-capi/CMakeLists.txt
@@ -155,20 +155,15 @@ get_version()
 set_target_properties(DPCTLSyclInterface
     PROPERTIES
         VERSION ${VERSION_MAJOR}.${VERSION_MINOR}
-        SOVERSION ${VERSION_MAJOR}
+        SOVERSION ${VERSION_MAJOR}.${VERSION_MINOR}
 )

 set(linker_script1
-    "INPUT(libDPCTLSyclInterface.so libDPCTLSyclInterface.so.${VERSION_MAJOR})"
-)
-set(linker_script2
-    "INPUT(libDPCTLSyclInterface.so.${VERSION_MAJOR} libDPCTLSyclInterface.so.${VERSION_MAJOR}.${VERSION_MINOR})"
+    "INPUT(libDPCTLSyclInterface.so.${VERSION_MAJOR}.${VERSION_MINOR})"
 )
 add_custom_command(TARGET DPCTLSyclInterface POST_BUILD
     COMMAND "${CMAKE_COMMAND}" -E remove "libDPCTLSyclInterface.so"
     COMMAND "${CMAKE_COMMAND}" -E echo "${linker_script1}" > "libDPCTLSyclInterface.so"
-    COMMAND "${CMAKE_COMMAND}" -E remove "libDPCTLSyclInterface.so.${VERSION_MAJOR}"
-    COMMAND "${CMAKE_COMMAND}" -E echo "${linker_script2}" > "libDPCTLSyclInterface.so.${VERSION_MAJOR}"
     VERBATIM
 )

I am able to run pytest and it passes on Linux locally.

[coveralls]

Coverage increased (+0.06%) to 60.728% when pulling 62d67cf on fix/linker_scripts into 414f0a6 on master.

[oleksandr-pavlyk]

BTW, will "${CMAKE_COMMAND}" -E echo "${linker_script1}" > "libDPCTLSyclInterface.so" also create a file on Windows?