ask for help about bison

[isaacson wang]

help-bison，

I using bison(2.3) to handle a .ypp file :

bison --skeleton=oaSpefParser.skl --name-prefix=Parser --defines
--file-prefix=oaSpefParser --report=itemset --verbose
--output=oaSpefParser.cpp oaSpefParser.ypp
In "oaSpefParser.skl" there are some marcos "b4_XXX", defined in c.m4 in the
same directory.
But after handling, marcos "b4_XXX" appeared in output file
oaSpefParser.cpp.
But when i used bison(1.875c), the marcos were handled. Why?

BR
Yue.wang