Wouldn't it be possible to change mit/config/imakemdep.h ?
Can't you do something like this:

--- piece of mit/config/imakemdep.h ----------
/*
 * Step 5:  cpp_argv
 *     The following table contains the cpp flags that should be passed to
 *     cpp whenever a Makefile is being generated.  If your preprocessor
 *     doesn't predefine any unique symbols, choose one and add it to the
 *     end of this table.  Then, do the following:
 *
 *         a.  Use this symbol at the top of Imake.tmpl when setting MacroFile.
 *         b.  Put this symbol in the definition of BootstrapCFlags in your
 *             <platform>.cf file.
 *         c.  When doing a make World, always add "BOOTSTRAPCFLAGS=-Dsymbol"
 *             to the end of the command line.
 *
 *     Note that you may define more than one symbols (useful for platforms
 *     that support multiple operating systems).
 */

#define ARGUMENTS 50    /* number of arguments in various arrays */
char *cpp_argv[ARGUMENTS] = {
#ifdef USE_CC_E
        "cc",           /* replaced by the actual cpp program to exec */
        "-E",
#else
        "cpp",          /* replaced by the actual cpp program to exec */
#endif /* USE_CC_E */
        "-I.",          /* add current directory to include path */
#ifdef unix
        "-Uunix",       /* remove unix symbol so that filename unix.c okay */
#endif


blablabla


#ifdef netbsd
	"-traditional",  /* netbsd */
#endif 


blablablablabla

---------- end piece of mit/config/imakemdep.h --------




John Vrolijk

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