diff --git a/Modules/FindBISON.cmake b/Modules/FindBISON.cmake
index bb1b577c1..6b1c7bd75 100644
--- a/Modules/FindBISON.cmake
+++ b/Modules/FindBISON.cmake
@@ -126,14 +126,47 @@ if(BISON_EXECUTABLE)
   endif()
 
   # internal macro
-  macro(BISON_TARGET_set_verbose_file BisonOutput)
-    get_filename_component(BISON_TARGET_output_path "${BisonOutput}" PATH)
-    get_filename_component(BISON_TARGET_output_name "${BisonOutput}" NAME_WE)
-    set(BISON_TARGET_verbose_file
-      "${BISON_TARGET_output_path}/${BISON_TARGET_output_name}.output")
+  # sets BISON_TARGET_cmdopt
+  macro(BISON_TARGET_option_extraopts Options)
+    set(BISON_TARGET_cmdopt "")
+    set(BISON_TARGET_extraopts "${Options}")
+    separate_arguments(BISON_TARGET_extraopts)
+    list(APPEND BISON_TARGET_cmdopt ${BISON_TARGET_extraopts})
   endmacro()
 
   # internal macro
+  # sets BISON_TARGET_output_header and BISON_TARGET_cmdopt
+  macro(BISON_TARGET_option_defines BisonOutput Header)
+    if("${Header}" STREQUAL "")
+      # default header path generated by bison (see option -d)
+      string(REGEX REPLACE "^(.*)(\\.[^.]*)$" "\\2" _fileext "${BisonOutput}")
+      string(REPLACE "c" "h" _fileext ${_fileext})
+      string(REGEX REPLACE "^(.*)(\\.[^.]*)$" "\\1${_fileext}"
+          BISON_TARGET_output_header "${BisonOutput}")
+      list(APPEND BISON_TARGET_cmdopt "-d")
+    else()
+      set(BISON_TARGET_output_header "${Header}")
+      list(APPEND BISON_TARGET_cmdopt "--defines=${BISON_TARGET_output_header}")
+    endif()
+  endmacro()
+
+  # internal macro
+  # sets BISON_TARGET_verbose_file and BISON_TARGET_cmdopt
+  macro(BISON_TARGET_option_report_file BisonOutput ReportFile)
+    if("${ReportFile}" STREQUAL "")
+      get_filename_component(BISON_TARGET_output_path "${BisonOutput}" PATH)
+      get_filename_component(BISON_TARGET_output_name "${BisonOutput}" NAME_WE)
+      set(BISON_TARGET_verbose_file
+        "${BISON_TARGET_output_path}/${BISON_TARGET_output_name}.output")
+    else()
+      set(BISON_TARGET_verbose_file "${ReportFile}")
+      list(APPEND BISON_TARGET_cmdopt "--report-file=${BISON_TARGET_verbose_file}")
+    endif()
+  endmacro()
+
+  # internal macro
+  # adds a custom command and sets
+  #   BISON_TARGET_cmdopt, BISON_TARGET_verbose_file, BISON_TARGET_extraoutputs
   macro(BISON_TARGET_option_verbose Name BisonOutput filename)
     list(APPEND BISON_TARGET_cmdopt "--verbose")
     list(APPEND BISON_TARGET_extraoutputs
@@ -154,35 +187,13 @@ if(BISON_EXECUTABLE)
     endif()
   endmacro()
 
-  # internal macro
-  macro(BISON_TARGET_option_extraopts Options)
-    set(BISON_TARGET_extraopts "${Options}")
-    separate_arguments(BISON_TARGET_extraopts)
-    list(APPEND BISON_TARGET_cmdopt ${BISON_TARGET_extraopts})
-  endmacro()
-
-  # internal macro
-  macro(BISON_TARGET_option_defines Header)
-    set(BISON_TARGET_output_header "${Header}")
-    list(APPEND BISON_TARGET_cmdopt "--defines=${BISON_TARGET_output_header}")
-  endmacro()
-
-  # internal macro
-  macro(BISON_TARGET_option_report_file ReportFile)
-    set(BISON_TARGET_verbose_file "${ReportFile}")
-    list(APPEND BISON_TARGET_cmdopt "--report-file=${BISON_TARGET_verbose_file}")
-  endmacro()
-
   #============================================================
   # BISON_TARGET (public macro)
   #============================================================
   #
   macro(BISON_TARGET Name BisonInput BisonOutput)
-    set(BISON_TARGET_output_header "")
-    set(BISON_TARGET_cmdopt "")
     set(BISON_TARGET_outputs "${BisonOutput}")
     set(BISON_TARGET_extraoutputs "")
-    BISON_TARGET_set_verbose_file("${BisonOutput}")
 
     # Parsing parameters
     set(BISON_TARGET_PARAM_OPTIONS
@@ -209,15 +220,10 @@ if(BISON_EXECUTABLE)
       # [VERBOSE [<file>] hack: <file> is non-multi value by usage
       message(SEND_ERROR "Usage")
     else()
-      if(NOT "${BISON_TARGET_ARG_COMPILE_FLAGS}" STREQUAL "")
-        BISON_TARGET_option_extraopts("${BISON_TARGET_ARG_COMPILE_FLAGS}")
-      endif()
-      if(NOT "${BISON_TARGET_ARG_DEFINES_FILE}" STREQUAL "")
-        BISON_TARGET_option_defines("${BISON_TARGET_ARG_DEFINES_FILE}")
-      endif()
-      if(NOT "${BISON_TARGET_ARG_REPORT_FILE}" STREQUAL "")
-        BISON_TARGET_option_report_file("${BISON_TARGET_ARG_REPORT_FILE}")
-      endif()
+
+      BISON_TARGET_option_extraopts("${BISON_TARGET_ARG_COMPILE_FLAGS}")
+      BISON_TARGET_option_defines("${BisonOutput}" "${BISON_TARGET_ARG_DEFINES_FILE}")
+      BISON_TARGET_option_report_file("${BisonOutput}" "${BISON_TARGET_ARG_REPORT_FILE}")
       if(NOT "${BISON_TARGET_ARG_VERBOSE}" STREQUAL "")
         BISON_TARGET_option_verbose(${Name} ${BisonOutput} "${BISON_TARGET_ARG_VERBOSE}")
       else()
@@ -230,14 +236,6 @@ if(BISON_EXECUTABLE)
         endif()
       endif()
 
-      if("${BISON_TARGET_output_header}" STREQUAL "")
-        # Header's name generated by bison (see option -d)
-        list(APPEND BISON_TARGET_cmdopt "-d")
-        string(REGEX REPLACE "^(.*)(\\.[^.]*)$" "\\2" _fileext "${BisonOutput}")
-        string(REPLACE "c" "h" _fileext ${_fileext})
-        string(REGEX REPLACE "^(.*)(\\.[^.]*)$" "\\1${_fileext}"
-            BISON_TARGET_output_header "${BisonOutput}")
-      endif()
       list(APPEND BISON_TARGET_outputs "${BISON_TARGET_output_header}")
 
       add_custom_command(OUTPUT ${BISON_TARGET_outputs}