poisened macro definitions

[Markus Franke]

Dear GCC Developers,

I want to port an existing backend (based on version gcc-2.7.2.3) on the
most recent release (gcc-4.1.1). During compilation process I get
several messages about some poisened macro definitions. The macros which
make problems are listed below:

---snip---
                        "CPP_PREDEFINES"
                        "TARGET_SWITCHES"
                        "EXTRA_CC_MODES"
                        "STRUCT_VALUE_REGNUM"
                        "NO_RECURSIVE_FUNCTION_CSE"
                        "FUNCTION_PROLOGUE"
                        "FUNCTION_EPILOGUE"
                        "TARGET_BELL"
                        "TARGET_BS"
                        "TARGET_TAB"
                        "TARGET_NEWLINE"
                        "TARGET_VT"
                        "TARGET_FF"
                        "TARGET_CR"
                        "EASY_DIV_EXPR"
                        "PREDICATE_CODES"
                        "CONST_COSTS"
                        "SELECT_RTX_SECTION"
                        "SELECT_SECTION"
                        "ASM_IDENTIFY_GCC"
                        "ASM_FILE_START"
                        "ASM_FILE_END"
                        "ASM_OPEN_PAREN"
                        "ASM_CLOSE_PAREN"
                        "ASM_GLOBALIZE_LABEL"
                        "FUNCTION_ARG_PARTIAL_NREGS"
--snap---

I read something about poisened macros and that they shouldn't be used
anymore. But in fact I was not able to find any documentation about
these macros. When were they declared as poisened and especially why?
What should be done instead of using this macros? Just uncommenting
everything can't be a solution. I was also looking in GCC-Internals
manual without any success.


Thanks for your help,
Markus Franke