Create make rules for INTERFACE_LIBRARY targets.

The result is that the depends of the target are created.

So,

 add_library(somelib foo.cpp)
 add_library(anotherlib EXCLUDE_FROM_ALL foo.cpp)
 add_library(extra EXCLUDE_FROM_ALL foo.cpp)
 target_link_libraries(anotherlib extra)

 add_library(iface INTERFACE)
 target_link_libraries(iface INTERFACE anotherlib)

Executing 'make iface' will result in the anotherlib and extra targets
being made.

Adding a regular executable to the INTERFACE of an INTERFACE_LIBRARY
will not result in the executable being built with 'make iface' because
of the logic in cmComputeTargetDepends::AddTargetDepend.

So far, this is implemented only for the Makefile generator. Other
generators will follow if this feature is possible for them.

Make INTERFACE_LIBRARY targets part of the all target by default.
Test this by building the all target and making the expected library
EXCLUDE_FROM_ALL.

1 files changed, 9 insertions, 1 deletions

diff --git a/Source/cmComputeTargetDepends.cxx b/Source/cmComputeTargetDepends.cxx
index 0829add..7fd4754 100644
--- a/Source/cmComputeTargetDepends.cxx
+++ b/Source/cmComputeTargetDepends.cxx
@@ -208,7 +208,15 @@ void cmComputeTargetDepends::CollectTargetDepends(int depender_index)
   std::set<cmStdString> emitted;
   {
   std::vector<std::string> tlibs;
-  depender->GetDirectLinkLibraries(0, tlibs, depender);
+  if (depender->GetType() == cmTarget::INTERFACE_LIBRARY)
+    {
+    // For INTERFACE_LIBRARY depend on the interface instead.
+    depender->GetInterfaceLinkLibraries(0, tlibs, depender);
+    }
+  else
+    {
+    depender->GetDirectLinkLibraries(0, tlibs, depender);
+    }
   // A target should not depend on itself.
   emitted.insert(depender->GetName());
   for(std::vector<std::string>::const_iterator lib = tlibs.begin();