Graphite header order

[David Edelsohn <dje dot gcc at gmail dot com>]

Sebastian,

I have tried to build GCC with Graphite and ISL on AIX and encountered
two problems:

(1) isl/ctx.h

typedef enum {
        isl_stat_error = -1,
        isl_stat_ok = 0,
} isl_stat;

GCC complains about the comma in "isl_stat_ok = 0,".  This seems like
a general bug that should appear on all targets.

(2) All of the graphite*.c files include ISL headers first.  This
order is not supported by GCC development and creates conflicts for
types and definitions provided / overridden by GCC headers, especially
system.h and its dependent headers like hwint.h.

I presume that ISL headers are included first is they use calloc() and
strdup(), which are poisoned by GCC in system.h.

I am uncertain of the exact header dependencies, but the primary
dependency seems to be that the ISL headers must be included before
graphite-poly.h.  The identifier poisoning problem needs to be
addressed by not poisoning the identifiers for files that include ISL
headers.  The Graphite files need some sort of a macro like

#define IN_GRAPHITE

or

#define IN_ISL

and system.h must not poison the identifiers when that macro is present.

I am going to try with a hack of bracketing system.h with #undef
IN_GCC / #define IN_GCC in the graphite files.

Thanks, David