diff --git a/qt4/src/CMakeLists.txt b/qt4/src/CMakeLists.txt
index 55ca97b0..24f56787 100644
--- a/qt4/src/CMakeLists.txt
+++ b/qt4/src/CMakeLists.txt
@@ -1,4 +1,5 @@
 add_definitions(${QT4_DEFINITIONS})
+add_definitions(-fvisibility=hidden -fvisibility-inlines-hidden -Dpoppler_qt4_EXPORTS)
 
 include_directories(
   ${CMAKE_CURRENT_SOURCE_DIR}
diff --git a/qt5/src/CMakeLists.txt b/qt5/src/CMakeLists.txt
index 113140a3..e38ac1b3 100644
--- a/qt5/src/CMakeLists.txt
+++ b/qt5/src/CMakeLists.txt
@@ -1,5 +1,6 @@
 add_definitions(${QT5_DEFINITIONS})
 add_definitions(${Qt5Core_DEFINITIONS})
+add_definitions(-fvisibility=hidden -fvisibility-inlines-hidden -Dpoppler_qt5_EXPORTS)
 
 include_directories(
   ${CMAKE_CURRENT_SOURCE_DIR}