diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index ed35fb8..30e6a98 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -1,107 +1,107 @@
 include_directories(${CMAKE_SOURCE_DIR} ${CMAKE_BINARY_DIR} ${CMAKE_CURRENT_BINARY_DIR} ${QT_INCLUDES})
 
 ## Compiler flags
 
 if(CMAKE_COMPILER_IS_GNUCXX)
-    set(CMAKE_C_FLAGS "-std=c99")   ## ALSA no longer compiles with -std=c90, see https://bugzilla.novell.com/show_bug.cgi?id=817077
+    set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -std=c99")   ## ALSA no longer compiles with -std=c90, see https://bugzilla.novell.com/show_bug.cgi?id=817077
 endif()
 
 find_package(Alsa)
 alsa_configure_file(${CMAKE_CURRENT_BINARY_DIR}/config-alsa.h)
 
 set(wmlib_audio_SRCS
         wmlib/audio/audio.c
         wmlib/audio/audio_arts.c
         wmlib/audio/audio_alsa.c
         wmlib/audio/audio_sun.c
 )
 
 set(wmlib_SRCS
         wmlib/cdda.c
         wmlib/cddb.c
         wmlib/cdrom.c
         wmlib/wm_helpers.c
         wmlib/cdtext.c
         wmlib/scsi.c
         wmlib/plat_aix.c
         wmlib/plat_bsd386.c
         wmlib/plat_freebsd.c
         wmlib/plat_hpux.c
         wmlib/plat_irix.c
         wmlib/plat_linux.c
         wmlib/plat_svr4.c
         wmlib/plat_ultrix.c
         wmlib/plat_news.c
         wmlib/plat_openbsd.c
         wmlib/plat_osf1.c
         wmlib/plat_sun.c
         wmlib/plat_scor5.c
         wmlib/drv_sony.c
         wmlib/drv_toshiba.c
 )
 
 if (APPLE OR WIN32 OR CMAKE_SYSTEM_NAME STREQUAL GNU)
         set(USE_WMLIB false)
 else (APPLE OR WIN32 OR CMAKE_SYSTEM_NAME STREQUAL GNU)
         set(USE_WMLIB true)
 endif (APPLE OR WIN32 OR CMAKE_SYSTEM_NAME STREQUAL GNU)
 
 set(KCD_LIB_SRCS
     kcompactdisc.cpp
     kcompactdisc_p.cpp
     phonon_interface.cpp
 )
 
 if (USE_WMLIB)
     set(KCD_LIB_SRCS ${KCD_LIB_SRCS} wmlib_interface.cpp ${wmlib_SRCS} ${wmlib_audio_SRCS})
     add_definitions(-DUSE_WMLIB=1)
 endif (USE_WMLIB)
 
 add_library(KF5CompactDisc SHARED ${KCD_LIB_SRCS})
 add_library(KF5::CompactDisc ALIAS KF5CompactDisc)
 set_target_properties(KF5CompactDisc PROPERTIES
     VERSION ${KCOMPACTDISC_VERSION}
     SOVERSION ${KCOMPACTDISC_SOVERSION}
     EXPORT_NAME CompactDisc
 )
 
 target_link_libraries(KF5CompactDisc
     Qt5::DBus
     KF5::CoreAddons
     KF5::Solid
     KF5::I18n
     Phonon::phonon4qt5
 )
 
 if (HAVE_LIBASOUND2)
     target_link_libraries(KF5CompactDisc ${ASOUND_LIBRARY})
 endif (HAVE_LIBASOUND2)
 
 if (USE_WMLIB)
     find_package(Threads)
     target_link_libraries(KF5CompactDisc ${CMAKE_THREAD_LIBS_INIT})
 endif (USE_WMLIB)
 
 target_include_directories(KF5CompactDisc INTERFACE "$<INSTALL_INTERFACE:${KDE_INSTALL_INCLUDEDIR_KF5}/KCompactDisc>")
 ecm_generate_headers(KCompactDisc_HEADERS
     HEADER_NAMES 
     KCompactDisc
     REQUIRED_HEADERS KCompactDisc_HEADERS
 )
 generate_export_header(KF5CompactDisc BASE_NAME KCompactDisc)
 
 ecm_generate_pri_file(
     BASE_NAME KCompactDisc
     LIB_NAME KF5CompactDisc
     DEPS "core dbus phonon4qt5 KCoreAddons KI18n Solid"
     FILENAME_VAR PRI_FILENAME
     INCLUDE_INSTALL_DIR ${KDE_INSTALL_INCLUDEDIR_KF5}/KCompactDisc
 )
 
 
 install(TARGETS KF5CompactDisc EXPORT KF5CompactDiscTargets ${KF5_INSTALL_TARGETS_DEFAULT_ARGS})
 install(FILES 
     ${CMAKE_CURRENT_BINARY_DIR}/kcompactdisc_export.h 
     ${KCompactDisc_HEADERS} 
     DESTINATION ${KDE_INSTALL_INCLUDEDIR_KF5}/KCompactDisc COMPONENT Devel)
 install(FILES ${PRI_FILENAME} DESTINATION ${ECM_MKSPECS_INSTALL_DIR})