[system] Add better flex dependencies to force regeneration with newer flex version

Author: gempa-jabe

Modules/flex.cmake

@@ -1,28 +1,35 @@
-# flex a .l file
-
-# search flex
-MACRO(FIND_FLEX)
-    IF(NOT FLEX_EXECUTABLE)
-        FIND_PROGRAM(FLEX_EXECUTABLE flex)
-        IF (NOT FLEX_EXECUTABLE)
-          MESSAGE(FATAL_ERROR "flex not found - aborting")
-        ENDIF (NOT FLEX_EXECUTABLE)
-    ENDIF(NOT FLEX_EXECUTABLE)
-ENDMACRO(FIND_FLEX)
-
-MACRO(ADD_FLEX_FILES _sources )
-    FIND_FLEX()
-    FOREACH (_current_FILE ${ARGN})
-	    GET_FILENAME_COMPONENT(_in ${_current_FILE} ABSOLUTE)
-	    GET_FILENAME_COMPONENT(_basename ${_current_FILE} NAME_WE)
-	    SET(_out ${CMAKE_CURRENT_BINARY_DIR}/flex_${_basename}.cc)
-	    ADD_CUSTOM_COMMAND(
-		    OUTPUT ${_out}
-		    COMMAND ${FLEX_EXECUTABLE}
-		      ARGS -o${_out} ${_in}
-		      DEPENDS ${_in} )
-	    SET(${_sources} ${${_sources}} ${_out} )
-    ENDFOREACH (_current_FILE)
-ENDMACRO(ADD_FLEX_FILES)
-
-
+# flex a .l file
+
+# search flex
+MACRO(FIND_FLEX)
+	IF(NOT FLEX_EXECUTABLE)
+		FIND_PROGRAM(FLEX_EXECUTABLE flex)
+		IF (NOT FLEX_EXECUTABLE)
+			MESSAGE(FATAL_ERROR "flex not found - aborting")
+		ENDIF (NOT FLEX_EXECUTABLE)
+	ENDIF(NOT FLEX_EXECUTABLE)
+
+	IF(NOT FLEX_INCLUDE_DIR)
+		FIND_PATH(FLEX_INCLUDE_DIR FlexLexer.h)
+		IF (NOT FLEX_INCLUDE_DIR)
+			MESSAGE(FATAL_ERROR "FlexLexer.h not found - aborting")
+		ENDIF (NOT FLEX_INCLUDE_DIR)
+	ENDIF (NOT FLEX_INCLUDE_DIR)
+ENDMACRO(FIND_FLEX)
+
+MACRO(ADD_FLEX_FILES _sources)
+	FIND_FLEX()
+	FOREACH (_current_FILE ${ARGN})
+		GET_FILENAME_COMPONENT(_in ${_current_FILE} ABSOLUTE)
+		GET_FILENAME_COMPONENT(_basename ${_current_FILE} NAME_WE)
+		SET(_out ${CMAKE_CURRENT_BINARY_DIR}/flex_${_basename}.cc)
+		ADD_CUSTOM_COMMAND(
+			OUTPUT ${_out}
+			COMMAND ${FLEX_EXECUTABLE}
+			ARGS -o${_out} ${_in}
+			DEPENDS ${_in} ${FLEX_EXECUTABLE} ${FLEX_INCLUDE_DIR}/FlexLexer.h)
+		SET(${_sources} ${${_sources}} ${_out})
+	ENDFOREACH (_current_FILE)
+ENDMACRO(ADD_FLEX_FILES)
+
+