ENH: Added CMAKE_LINK_OLD_PATHS compatibility mode for linker search paths.

1 files changed, 18 insertions, 0 deletions

diff --git a/Source/cmDocumentVariables.cxx b/Source/cmDocumentVariables.cxx
index 33b0a6e..4c33014 100644
--- a/Source/cmDocumentVariables.cxx
+++ b/Source/cmDocumentVariables.cxx
@@ -784,6 +784,24 @@ void cmDocumentVariables::DefineVariables(cmake* cm)
      "This is needed only on very few platforms.", false,
      "Variables that Control the Build");
   cm->DefineProperty
+    ("CMAKE_LINK_OLD_PATHS", cmProperty::VARIABLE,
+     "Enable linker search path compatibility mode.",
+     "This option enables linking compatibility mode for broken projects.  "
+     "There exists code that effectively does\n"
+     "  target_link_libraries(myexe /path/to/libA.so -lB)\n"
+     "where -lB is meant to link to /path/to/libB.so.  This is broken "
+     "because it specifies -lB without adding \"/path/to\" to the linker "
+     "search path with the link_directories command.  With CMake 2.4 and "
+     "below the code worked accidentally because \"/path/to\" would be "
+     "added to the linker search path by its implementation of linking to "
+     "/path/to/libA.so (which passed -L/path/to -lA to the linker).  "
+     "This option tells CMake to add the directories containing libraries "
+     "specified with a full path to the linker search path if the link "
+     "line contains any items like -lB.  "
+     "The behavior is also enabled if CMAKE_BACKWARDS_COMPATIBILITY is "
+     "set to 2.4 or lower.", false,
+     "Variables that Control the Build");
+  cm->DefineProperty
     ("CMAKE_USE_RELATIVE_PATHS", cmProperty::VARIABLE,
      "Use relative paths (May not work!).",
      "If this is set to TRUE, then the CMake will use "