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Postings from February 2006
On Feb 16, 2006, at 19:24, Andy Dougherty wrote: >> sizeof(opcode_t) != sizeof(void*) is for sure broken. > > Well, it used to work, but that was a long time ago. Configure > actually > tests for this case and still claims it will work; perhaps that test > should be changed to emit a much more dire message, or even die (unless > overridden). It's not really easy to state, which type combinations are valid, because the combinations depend on other config options. Given that current type abuse in parrot were fixed, we'd have these constraints: sizeof(opcode_t) >= sizeof(INTVAL) [1] sizeof(void *) >= sizeof(INTVAL) [2] [1] We are storing INTVAL constants in the opcode stream directly. Moving INTVAL constants into the constant table or decode INTVAL constants with more than one opcode would fix that [2] The direct threaded run core (CGP) is using labels as values, which are 'void *' according to 'info gcc'. The prederefed opcode stream also contains INTVAL constants. If the C compiler doesn't provide this feature there is still the prederefed switched runcore where a mix of (opcode_t, INTVAL, and void*) is in the opcode stream, but that could be a max-sized type probably. I hope that makes some sense, leoThread Previous | Thread Next