Fix #643

Author: Sbozzolo

CMakeLists.txt

@@ -49,7 +49,7 @@ if (USE_SYSTEM_LIBVTERM)
     endif()
     execute_process(COMMAND  grep -c "sb_clear" "${LIBVTERM_INCLUDE_DIR}/vterm.h" OUTPUT_VARIABLE VTermSBClearExists)
     if (${VTermSBClearExists} EQUAL "0")
-      add_definitions(-VTermSBClearNotExists)
+      add_definitions(-DVTermSBClearNotExists)
     endif()
   else()
     message(STATUS "System libvterm not found: libvterm will be downloaded and compiled as part of the build process")