From 617ee7c567128edaeba3a4947c48249182d345c5 Mon Sep 17 00:00:00 2001
From: Stephen Kelly <steveire@gmail.com>
Date: Wed, 18 Sep 2013 17:30:55 +0200
Subject: [PATCH] Add a test for SYSTEM headers in INTERFACE libraries.

---
 .../SystemIncludeDirectories/CMakeLists.txt   | 28 +++++++++++++++++++
 .../imported_consumer.cpp                     |  7 +++++
 .../systemlib_header_only/systemlib.h         | 16 +++++++++++
 3 files changed, 51 insertions(+)
 create mode 100644 Tests/IncludeDirectories/SystemIncludeDirectories/imported_consumer.cpp
 create mode 100644 Tests/IncludeDirectories/SystemIncludeDirectories/systemlib_header_only/systemlib.h

diff --git a/Tests/IncludeDirectories/SystemIncludeDirectories/CMakeLists.txt b/Tests/IncludeDirectories/SystemIncludeDirectories/CMakeLists.txt
index aec6ff981..1f5c93b44 100644
--- a/Tests/IncludeDirectories/SystemIncludeDirectories/CMakeLists.txt
+++ b/Tests/IncludeDirectories/SystemIncludeDirectories/CMakeLists.txt
@@ -17,3 +17,31 @@ target_include_directories(upstream SYSTEM PUBLIC
 add_library(consumer consumer.cpp)
 target_link_libraries(consumer upstream)
 target_compile_options(consumer PRIVATE -Werror=unused-variable)
+
+add_library(iface IMPORTED INTERFACE)
+set_property(TARGET iface PROPERTY INTERFACE_INCLUDE_DIRECTORIES "${CMAKE_CURRENT_SOURCE_DIR}/systemlib_header_only")
+
+add_library(imported_consumer imported_consumer.cpp)
+target_link_libraries(imported_consumer iface)
+target_compile_options(imported_consumer PRIVATE -Werror=unused-variable)
+
+macro(do_try_compile error_option)
+  set(TC_ARGS
+    IFACE_TRY_COMPILE_${error_option}
+    "${CMAKE_CURRENT_BINARY_DIR}/try_compile_iface" "${CMAKE_CURRENT_SOURCE_DIR}/imported_consumer.cpp"
+    LINK_LIBRARIES iface
+  )
+  if (${error_option} STREQUAL WITH_ERROR)
+    list(APPEND TC_ARGS COMPILE_DEFINITIONS -Werror=unused-variable)
+  endif()
+  try_compile(${TC_ARGS})
+endmacro()
+
+do_try_compile(NO_ERROR)
+if (NOT IFACE_TRY_COMPILE_NO_ERROR)
+  message(SEND_ERROR "try_compile failed with imported target.")
+endif()
+do_try_compile(WITH_ERROR)
+if (NOT IFACE_TRY_COMPILE_WITH_ERROR)
+  message(SEND_ERROR "try_compile failed with imported target with error option.")
+endif()
diff --git a/Tests/IncludeDirectories/SystemIncludeDirectories/imported_consumer.cpp b/Tests/IncludeDirectories/SystemIncludeDirectories/imported_consumer.cpp
new file mode 100644
index 000000000..1dbe819e1
--- /dev/null
+++ b/Tests/IncludeDirectories/SystemIncludeDirectories/imported_consumer.cpp
@@ -0,0 +1,7 @@
+
+#include "systemlib.h"
+
+int main()
+{
+  return systemlib();
+}
diff --git a/Tests/IncludeDirectories/SystemIncludeDirectories/systemlib_header_only/systemlib.h b/Tests/IncludeDirectories/SystemIncludeDirectories/systemlib_header_only/systemlib.h
new file mode 100644
index 000000000..93622c433
--- /dev/null
+++ b/Tests/IncludeDirectories/SystemIncludeDirectories/systemlib_header_only/systemlib.h
@@ -0,0 +1,16 @@
+
+#ifndef SYSTEMLIB_H
+#define SYSTEMLIB_H
+
+int systemlib()
+{
+  return 0;
+}
+
+int unusedFunc()
+{
+  int unused;
+  return systemlib();
+}
+
+#endif