Add the INTERFACE_SYSTEM_INCLUDE_DIRECTORIES target property.

Unlike other target properties, this does not have a corresponding
non-INTERFACE variant.

This allows propagation of system attribute on include directories
from link dependents.

6 files changed, 65 insertions, 0 deletions

diff --git a/Tests/IncludeDirectories/SystemIncludeDirectories/CMakeLists.txt b/Tests/IncludeDirectories/SystemIncludeDirectories/CMakeLists.txt
new file mode 100644
index 0000000..aec6ff9
--- /dev/null
+++ b/Tests/IncludeDirectories/SystemIncludeDirectories/CMakeLists.txt
@@ -0,0 +1,19 @@
+
+cmake_minimum_required(VERSION 2.8)
+
+project(SystemIncludeDirectories)
+
+add_library(systemlib systemlib.cpp)
+target_include_directories(systemlib PUBLIC "${CMAKE_CURRENT_SOURCE_DIR}/systemlib")
+
+add_library(upstream upstream.cpp)
+target_link_libraries(upstream LINK_PUBLIC systemlib)
+target_compile_options(upstream PRIVATE -Werror=unused-variable)
+
+target_include_directories(upstream SYSTEM PUBLIC
+  $<TARGET_PROPERTY:systemlib,INTERFACE_INCLUDE_DIRECTORIES>
+)
+
+add_library(consumer consumer.cpp)
+target_link_libraries(consumer upstream)
+target_compile_options(consumer PRIVATE -Werror=unused-variable)
diff --git a/Tests/IncludeDirectories/SystemIncludeDirectories/consumer.cpp b/Tests/IncludeDirectories/SystemIncludeDirectories/consumer.cpp
new file mode 100644
index 0000000..197dae8
--- /dev/null
+++ b/Tests/IncludeDirectories/SystemIncludeDirectories/consumer.cpp
@@ -0,0 +1,7 @@
+
+#include "upstream.h"
+
+int consumer()
+{
+  return upstream();
+}
diff --git a/Tests/IncludeDirectories/SystemIncludeDirectories/systemlib.cpp b/Tests/IncludeDirectories/SystemIncludeDirectories/systemlib.cpp
new file mode 100644
index 0000000..f111bfa
--- /dev/null
+++ b/Tests/IncludeDirectories/SystemIncludeDirectories/systemlib.cpp
@@ -0,0 +1,4 @@
+
+#include "systemlib.h"
+
+int systemlib() { return 0; }
diff --git a/Tests/IncludeDirectories/SystemIncludeDirectories/systemlib/systemlib.h b/Tests/IncludeDirectories/SystemIncludeDirectories/systemlib/systemlib.h
new file mode 100644
index 0000000..c84de6a
--- /dev/null
+++ b/Tests/IncludeDirectories/SystemIncludeDirectories/systemlib/systemlib.h
@@ -0,0 +1,19 @@
+
+#ifndef SYSTEMLIB_H
+#define SYSTEMLIB_H
+
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+int systemlib();
+
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+int unusedFunc()
+{
+  int unused;
+  return systemlib();
+}
+
+#endif
diff --git a/Tests/IncludeDirectories/SystemIncludeDirectories/upstream.cpp b/Tests/IncludeDirectories/SystemIncludeDirectories/upstream.cpp
new file mode 100644
index 0000000..f716b99
--- /dev/null
+++ b/Tests/IncludeDirectories/SystemIncludeDirectories/upstream.cpp
@@ -0,0 +1,4 @@
+
+#include "upstream.h"
+
+int upstream() { return systemlib(); }
diff --git a/Tests/IncludeDirectories/SystemIncludeDirectories/upstream.h b/Tests/IncludeDirectories/SystemIncludeDirectories/upstream.h
new file mode 100644
index 0000000..3628568
--- /dev/null
+++ b/Tests/IncludeDirectories/SystemIncludeDirectories/upstream.h
@@ -0,0 +1,12 @@
+
+#ifndef UPSTREAM_H
+#define UPSTREAM_H
+
+#include "systemlib.h"
+
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+int upstream();
+
+#endif