diff --git a/CMakeLists.txt b/CMakeLists.txt
index e505e78..166f62d 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -109,7 +109,9 @@ install(FILES ${CMAKE_CURRENT_BINARY_DIR}/libxisf.pc DESTINATION ${CMAKE_INSTALL
 install(TARGETS XISF LIBRARY DESTINATION ${CMAKE_INSTALL_LIBDIR})
 
 list(JOIN PC_LIBS_REQUIRE ", " PC_REQUIRE_STR2)
-string(REPLACE "lz4" "liblz4" PC_REQUIRE_STR ${PC_REQUIRE_STR2})
+if(NOT PC_REQUIRE_STR2 STREQUAL "")
+    string(REPLACE "lz4" "liblz4" PC_REQUIRE_STR ${PC_REQUIRE_STR2})
+endif()
 list(TRANSFORM PC_LIBS_REQUIRE PREPEND "-l")
 list(JOIN PC_LIBS_REQUIRE " " PC_LIBS_STR)
 configure_file(libxisf.pc.in libxisf.pc @ONLY)