diff --git a/fortran/src/CMakeLists.txt b/fortran/src/CMakeLists.txt
index f8e25b5b392..b72e7f514c4 100644
--- a/fortran/src/CMakeLists.txt
+++ b/fortran/src/CMakeLists.txt
@@ -361,6 +361,8 @@ endif ()
 if (BUILD_SHARED_LIBS)
   if(MSVC)
       set(DLLDEF ${HDF5_F90_SRC_BINARY_DIR}/hdf5_fortrandll.def)
+  else()
+      set(DLLDEF "")
   endif()
   add_library (${HDF5_F90_LIBSH_TARGET} SHARED ${DLLDEF} ${f90_F_SOURCES_SHARED})
   target_include_directories (${HDF5_F90_LIBSH_TARGET}
diff --git a/hl/fortran/src/CMakeLists.txt b/hl/fortran/src/CMakeLists.txt
index 363003e0660..38c742fd714 100644
--- a/hl/fortran/src/CMakeLists.txt
+++ b/hl/fortran/src/CMakeLists.txt
@@ -200,6 +200,8 @@ endif ()
 if (BUILD_SHARED_LIBS)
   if(MSVC)
       set(DLLDEF ${HDF5_HL_F90_SRC_BINARY_DIR}/hdf5_hl_fortrandll.def)
+  else()
+      set(DLLDEF "")
   endif()
   add_library (${HDF5_HL_F90_LIBSH_TARGET} SHARED ${DLLDEF} ${HDF5_HL_F90_F_SOURCES_SHARED})
   target_include_directories (${HDF5_HL_F90_LIBSH_TARGET}