question on cpp-highlight-buffer

[Francis Moreau]

Hello,

I'm playing with this command, and if I understood it correctly I need to
define in the buffer named "*CPP Edit*" which macro (conditionnals) is true,
false or both if I don't know.

I'm wondering why this isn't done automatically by using cpp. The command
c-macro-expand already does this.

Does anyone know if it's possible ?

BTW, c-macro-expand command seems broken for this case:

$ cat file.c<<EOF
#define A_TAG 1

#ifdef A_TAG
EOF
$

if I select only "A_TAG" in the last line, runing the expand macro command
fails.

Thanks
-- 
Francis