From 6fbe3ce4ef1178cc4f2f14f281cd48ef82a11e03 Mon Sep 17 00:00:00 2001
From: Stephen Kelly <steveire@gmail.com>
Date: Wed, 23 Jan 2013 22:17:14 +0100
Subject: [PATCH] Exclude the LINK_LIBRARIES related properties from INTERFACE
 evaluation.

These interface-related link-libraries properties are used to determine
the value of the other INTERFACE properties, so we were getting infinite
recursion and segfaults otherwise.
---
 Source/cmGeneratorExpressionDAGChecker.cxx | 10 ++++++++--
 Tests/CompatibleInterface/CMakeLists.txt   | 16 ++++++++++++++++
 Tests/CompatibleInterface/iface2.cpp       |  7 +++++++
 Tests/CompatibleInterface/iface2.h         | 13 +++++++++++++
 Tests/CompatibleInterface/main.cpp         |  5 ++++-
 5 files changed, 48 insertions(+), 3 deletions(-)
 create mode 100644 Tests/CompatibleInterface/iface2.cpp
 create mode 100644 Tests/CompatibleInterface/iface2.h

diff --git a/Source/cmGeneratorExpressionDAGChecker.cxx b/Source/cmGeneratorExpressionDAGChecker.cxx
index 057f4c3d5..269211b92 100644
--- a/Source/cmGeneratorExpressionDAGChecker.cxx
+++ b/Source/cmGeneratorExpressionDAGChecker.cxx
@@ -114,8 +114,14 @@ bool cmGeneratorExpressionDAGChecker::EvaluatingLinkLibraries()
   const cmGeneratorExpressionDAGChecker *parent = this->Parent;
   while (parent)
     {
-    parent = parent->Parent;
     top = parent;
+    parent = parent->Parent;
     }
-  return top->Property == "LINK_LIBRARIES";
+
+  const char *prop = top->Property.c_str();
+  return (strcmp(prop, "LINK_LIBRARIES") == 0
+       || strcmp(prop, "LINK_INTERFACE_LIBRARIES") == 0
+       || strcmp(prop, "IMPORTED_LINK_INTERFACE_LIBRARIES") == 0
+       || strncmp(prop, "LINK_INTERFACE_LIBRARIES_", 26) == 0
+       || strncmp(prop, "IMPORTED_LINK_INTERFACE_LIBRARIES_", 35) == 0);
 }
diff --git a/Tests/CompatibleInterface/CMakeLists.txt b/Tests/CompatibleInterface/CMakeLists.txt
index d0eb60f25..728065231 100644
--- a/Tests/CompatibleInterface/CMakeLists.txt
+++ b/Tests/CompatibleInterface/CMakeLists.txt
@@ -3,12 +3,16 @@ cmake_minimum_required(VERSION 2.8)
 
 project(CompatibleInterface)
 
+include(GenerateExportHeader)
+set(CMAKE_INCLUDE_CURRENT_DIR ON)
+
 add_library(iface1 empty.cpp)
 set_property(TARGET iface1 APPEND PROPERTY
   COMPATIBLE_INTERFACE_BOOL
     BOOL_PROP1
     BOOL_PROP2
     BOOL_PROP3
+    BOOL_PROP4
 )
 
 set_property(TARGET iface1 PROPERTY INTERFACE_BOOL_PROP1 ON)
@@ -26,3 +30,15 @@ target_compile_definitions(CompatibleInterface
     $<$<BOOL:$<TARGET_PROPERTY:BOOL_PROP2>>:BOOL_PROP2>
     $<$<BOOL:$<TARGET_PROPERTY:BOOL_PROP3>>:BOOL_PROP3>
 )
+
+
+add_library(iface2 SHARED iface2.cpp)
+generate_export_header(iface2)
+
+# For the LINK_LIBRARIES and related properties, we should not evaluate
+# properties defined only in the interface - they should be implicitly zero
+set_property(TARGET iface2
+  APPEND PROPERTY
+    LINK_INTERFACE_LIBRARIES $<$<BOOL:$<TARGET_PROPERTY:BOOL_PROP4>>:nonexistant>
+)
+target_link_libraries(CompatibleInterface iface2)
diff --git a/Tests/CompatibleInterface/iface2.cpp b/Tests/CompatibleInterface/iface2.cpp
new file mode 100644
index 000000000..a9b501508
--- /dev/null
+++ b/Tests/CompatibleInterface/iface2.cpp
@@ -0,0 +1,7 @@
+
+#include "iface2.h"
+
+int Iface2::foo()
+{
+  return 0;
+}
diff --git a/Tests/CompatibleInterface/iface2.h b/Tests/CompatibleInterface/iface2.h
new file mode 100644
index 000000000..ef4ebeec2
--- /dev/null
+++ b/Tests/CompatibleInterface/iface2.h
@@ -0,0 +1,13 @@
+
+#ifndef IFACE2_H
+#define IFACE2_H
+
+#include "iface2_export.h"
+
+class IFACE2_EXPORT Iface2
+{
+public:
+  int foo();
+};
+
+#endif
diff --git a/Tests/CompatibleInterface/main.cpp b/Tests/CompatibleInterface/main.cpp
index b7c66386c..ae0e985c8 100644
--- a/Tests/CompatibleInterface/main.cpp
+++ b/Tests/CompatibleInterface/main.cpp
@@ -11,7 +11,10 @@
 #error Expected BOOL_PROP3
 #endif
 
+#include "iface2.h"
+
 int main(int argc, char **argv)
 {
-  return 0;
+  Iface2 if2;
+  return if2.foo();
 }