Merge topic 'gnu-visibility-aix'

e1f0518d GNU: Use -fvisibility on AIX when supported
eae0a85d Tests: Remove redundant code from RunCMake.GenerateExportHeader case

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !1659

Modules/Platform/AIX-GNU.cmake

@@ -24,5 +24,7 @@ macro(__aix_compiler_gnu lang)
   set(CMAKE_${lang}_USE_IMPLICIT_LINK_DIRECTORIES_IN_RUNTIME_PATH 1)
 
   set(CMAKE_${lang}_LINK_FLAGS "-Wl,-bnoipath")
-  unset(CMAKE_${lang}_COMPILE_OPTIONS_VISIBILITY)
+  if(CMAKE_${lang}_COMPILER_VERSION VERSION_LESS 7 OR CMAKE_SYSTEM_VERSION VERSION_LESS 7.1)
+    unset(CMAKE_${lang}_COMPILE_OPTIONS_VISIBILITY)
+  endif()
 endmacro()

Tests/RunCMake/GenerateExportHeader/GEH.cmake

@@ -53,7 +53,16 @@ endif()
 
 add_subdirectory(lib_shared_and_static)
 
-add_compiler_export_flags()
+if(CMAKE_SYSTEM_NAME MATCHES "AIX" AND CMAKE_CXX_COMPILER_ID STREQUAL "GNU"
+   AND CMAKE_CXX_COMPILE_OPTIONS_VISIBILITY)
+  # With GNU 7 on AIX, passing -fvisibility=hidden when driving the
+  # linker for a shared library drops the so init/destruct symbols.
+  # Just use the modern approach instead of testing the macro.
+  set(CMAKE_CXX_VISIBILITY_PRESET hidden)
+  set(CMAKE_VISIBILITY_INLINES_HIDDEN 1)
+else()
+  add_compiler_export_flags()
+endif()
 
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_CURRENT_BINARY_DIR})
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY_DEBUG ${CMAKE_CURRENT_BINARY_DIR})

Tests/RunCMake/GenerateExportHeader/libshared/CMakeLists.txt

@@ -1,7 +1,5 @@
 include(GenerateExportHeader)
 
-add_compiler_export_flags()
-
 set(CMAKE_INCLUDE_CURRENT_DIR ON)
 
 add_library(libshared SHARED libshared.cpp)

Tests/RunCMake/GenerateExportHeader/libstatic/CMakeLists.txt

@@ -2,8 +2,6 @@ set(CMAKE_INCLUDE_CURRENT_DIR ON)
 
 include(GenerateExportHeader)
 
-add_compiler_export_flags()
-
 # Show that the export header has no effect on a static library.
 
 add_library(libstatic STATIC libstatic.cpp)