Export the INTERFACE_PIC property.

Source/cmExportBuildFileGenerator.cxx

@@ -72,6 +72,8 @@ bool cmExportBuildFileGenerator::GenerateMainFile(std::ostream& os)
     this->PopulateInterfaceProperty("INTERFACE_COMPILE_DEFINITIONS", te,
                                     cmGeneratorExpression::BuildInterface,
                                     properties, missingTargets);
+    this->PopulateInterfaceProperty("INTERFACE_POSITION_INDEPENDENT_CODE",
+                                  te, properties);
 
     this->GenerateInterfaceProperties(te, os, properties);
     }

Source/cmExportFileGenerator.cxx

@@ -125,6 +125,18 @@ void cmExportFileGenerator::GenerateImportConfig(std::ostream& os,
   this->GenerateImportTargetsConfig(os, config, suffix, missingTargets);
 }
 
+//----------------------------------------------------------------------------
+void cmExportFileGenerator::PopulateInterfaceProperty(const char *propName,
+                                              cmTarget *target,
+                                              ImportPropertyMap &properties)
+{
+  const char *input = target->GetProperty(propName);
+  if (input)
+    {
+    properties[propName] = input;
+    }
+}
+
 //----------------------------------------------------------------------------
 void cmExportFileGenerator::PopulateInterfaceProperty(const char *propName,
                       const char *outputName,

Source/cmExportFileGenerator.h

@@ -101,6 +101,8 @@ protected:
                                  cmGeneratorExpression::PreprocessContext,
                                  ImportPropertyMap &properties,
                                  std::vector<std::string> &missingTargets);
+  void PopulateInterfaceProperty(const char *propName, cmTarget *target,
+                                 ImportPropertyMap &properties);
   void GenerateInterfaceProperties(cmTarget *target, std::ostream& os,
                                    const ImportPropertyMap &properties);
 

Source/cmExportInstallFileGenerator.cxx

@@ -89,6 +89,8 @@ bool cmExportInstallFileGenerator::GenerateMainFile(std::ostream& os)
                                   te,
                                   cmGeneratorExpression::InstallInterface,
                                   properties, missingTargets);
+    this->PopulateInterfaceProperty("INTERFACE_POSITION_INDEPENDENT_CODE",
+                                  te, properties);
 
     this->GenerateInterfaceProperties(te, os, properties);
     }

Tests/ExportImport/Export/CMakeLists.txt

@@ -162,6 +162,10 @@ include(GenerateExportHeader)
 
 add_library(testSharedLibRequired SHARED testSharedLibRequired.cpp)
 generate_export_header(testSharedLibRequired)
+set_property(TARGET testSharedLibRequired
+  PROPERTY
+    INTERFACE_POSITION_INDEPENDENT_CODE ON
+)
 set_property(TARGET testSharedLibRequired APPEND PROPERTY
   INCLUDE_DIRECTORIES "${CMAKE_CURRENT_BINARY_DIR}"
 )

Tests/ExportImport/Import/A/CMakeLists.txt

@@ -167,6 +167,24 @@ target_link_libraries(deps_shared_iface testSharedLibDepends)
 target_include_directories(deps_shared_iface PRIVATE testSharedLibDepends)
 target_compile_definitions(deps_shared_iface PRIVATE testSharedLibDepends)
 
+if (APPLE OR CMAKE_CXX_COMPILER_ID MATCHES "GNU")
+  include(CheckCXXCompilerFlag)
+  check_cxx_compiler_flag(-fPIE run_pic_test)
+else()
+  if (CMAKE_CXX_COMPILER_ID MATCHES "PGI"
+      OR CMAKE_CXX_COMPILER_ID MATCHES "PathScale"
+      OR CMAKE_SYSTEM_NAME MATCHES "IRIX64"
+      OR CMAKE_CXX_COMPILER_ID MATCHES "Intel")
+    set(run_pic_test 0)
+  else()
+    set(run_pic_test 1)
+  endif()
+endif()
+
+if (run_pic_test)
+  target_compile_definitions(deps_shared_iface PRIVATE CHECK_PIC_WORKS)
+endif()
+
 #-----------------------------------------------------------------------------
 # Test that targets imported from the build tree have their dependencies
 # evaluated correctly. The above already tests the same for the install tree.

Tests/ExportImport/Import/A/deps_shared_iface.cpp

@@ -2,6 +2,12 @@
 
 #include "testSharedLibDepends.h"
 
+#ifdef CHECK_PIC_WORKS
+#if defined(__ELF__) && !defined(__PIC__) && !defined(__PIE__)
+#error Expected by INTERFACE_POSITION_INDEPENDENT_CODE property of dependency
+#endif
+#endif
+
 #ifdef TEST_SUBDIR_LIB
 #include "subdir.h"
 #endif