[test-suite] Append LDFLAGS to LINK_LIBRARIES

[mcrosier]

Summary

r261397 changed how LDFLAGS were added to the target under cmake from
using target_link_libraries to using a function to call
append_target_flags to append LDFLAGS to LINK_FLAGS because
target_link_libraries ignores flags that do not begin with -; however,
LINK_FLAGS are appended before the object files on the link line, so
this causes linking statically to fail.

This patches changes the append_compile_flags macro to append LDFLAGS to
LINK_LIBRARIES instead of LINK_FLAGS, as LINK_LIBRARIES is appended
after the object files. In addition, it modifies the append_target_flags
macro to strip whitespace before setting the destination variable, as
having any whitespace before or after LINK_LIBRARIES violates CMP0004.

[MatzeB]

Have you tried what happens when we change the append_link_flags macro to:

macro(append_link_flags target)
  append_target_flags(LINK_LIBRARIES ${target} ${ARGN})
endmacro()

My understanding from the cmake docu is that those get appended after the object files, what is not clear to me from the docu is whether we get the same stupid behavior as target_link_libraries() but I think there is a chance that the target property is just appended without cmake trying to be smart...

[mcrosier]

Update based on Matthias' comments.

[MatzeB]

Tried this and it works fine for me (the -Xlinker 0x800000 that made switch away from target_link_library() is still passed correctly to the linker).
LGTM.

cmake/modules/SingleMultiSource.cmake

243

accidental newline?

[mcrosier]

Committed r263235. Thanks, Matthias.

cmake/modules/SingleMultiSource.cmake

     string(REPLACE " " "\\ " quoted "${ARGN}")
     string(REPLACE "\"" "\\\"" quoted "${quoted}")
     string(REPLACE ";" " " quoted "${quoted}")
-    set_target_properties(${target} PROPERTIES ${propertyname} "${old_flags} ${quoted}")
+    # Ensure that there is no leading or trailing whitespace
+    # This is especially important if old_flags is empty and the property
+    # is LINK_LIBRARIES, as extra whitespace violates CMP0004
+    string(STRIP "${old_flags} ${quoted}" new_flags)
+    set_target_properties(${target} PROPERTIES ${propertyname} "${new_flags}")
   endif()
 endmacro()
 

 endmacro()
 
 macro(append_link_flags target)
-  append_target_flags(LINK_FLAGS ${target} ${ARGN})
+  append_target_flags(LINK_LIBRARIES ${target} ${ARGN})
 endmacro()
 
 # llvm_add_test - Create a .test driver file suitable for LIT.

     set(TESTSCRIPT "${TESTSCRIPT}METRIC: ${ARGS_METRIC}: ${JOINED_ARGUMENTS}\n")
   endif()
 endmacro()
-  
+