Handle INTERFACE properties transitively for includes and defines.

Contextually, the behavior is as if the properties content from another
target is included in the string and then the result is evaluated.

1 files changed, 29 insertions, 1 deletions

diff --git a/Source/cmGeneratorExpressionEvaluator.cxx b/Source/cmGeneratorExpressionEvaluator.cxx
index 4b44ebe..b7ce155 100644
--- a/Source/cmGeneratorExpressionEvaluator.cxx
+++ b/Source/cmGeneratorExpressionEvaluator.cxx
@@ -286,6 +286,13 @@ static const struct ConfigurationTestNode : public cmGeneratorExpressionNode
   }
 } configurationTestNode;
 
+
+//----------------------------------------------------------------------------
+static const char* targetPropertyTransitiveWhitelist[] = {
+    "INTERFACE_INCLUDE_DIRECTORIES"
+  , "INTERFACE_COMPILE_DEFINITIONS"
+};
+
 //----------------------------------------------------------------------------
 static const struct TargetPropertyNode : public cmGeneratorExpressionNode
 {
@@ -394,7 +401,28 @@ static const struct TargetPropertyNode : public cmGeneratorExpressionNode
       }
 
     const char *prop = target->GetProperty(propertyName.c_str());
-    return prop ? prop : "";
+    if (!prop)
+      {
+      return std::string();
+      }
+
+    for (size_t i = 0;
+         i < (sizeof(targetPropertyTransitiveWhitelist) /
+              sizeof(*targetPropertyTransitiveWhitelist));
+         ++i)
+      {
+      if (targetPropertyTransitiveWhitelist[i] == propertyName)
+        {
+        cmGeneratorExpression ge(context->Backtrace);
+        return ge.Parse(prop)->Evaluate(context->Makefile,
+                            context->Config,
+                            context->Quiet,
+                            context->HeadTarget,
+                            target,
+                            &dagChecker);
+        }
+      }
+    return prop;
   }
 } targetPropertyNode;