assertion in headers.c breaks OS X

[Nicholas Clark]

For some reason this change to src/headers.c breaks on OS X. I'm not sure
why:

@@ -244,6 +245,7 @@
     pool = flags & PObj_constant_FLAG ?
         interpreter->arena_base->constant_pmc_pool :
         interpreter->arena_base->pmc_pool;
+    assert(sizeof(Dead_PObj) <= sizeof(PMC));
     pmc = pool->get_free_object(interpreter, pool);
     /* clear flags, set is_PMC_FLAG */
     if (flags & PObj_is_PMC_EXT_FLAG) {



src/headers.c
src/headers.c: In function `new_pmc_header':
src/headers.c:248: error: `Dead_PObj' undeclared (first use in this function)
src/headers.c:248: error: (Each undeclared identifier is reported only once
src/headers.c:248: error: for each function it appears in.)

$ gcc -v
Reading specs from /usr/libexec/gcc/darwin/ppc/3.3/specs
Thread model: posix
gcc version 3.3 20030304 (Apple Computer, Inc. build 1495)


It doesn't seem to fail on Linux (with notgcc 2.96) so I'm somewhat at a loss
as to what to fix.

Nicholas Clark