Richard Henderson <[email protected]> writes: > On 04/23/2014 03:17 AM, Petr Machata wrote: >> Wouldn't something like this get us off the hook as well? >> >> - (var) |= (typeof (var)) __s.i << ((nth) * 7); \ >> + (var) |= (typeof (var)) \ >> + (((uint64_t) (typeof (var)) __s.i) << ((nth) * 7)); \ >> >> We are really only using the bitfield trick to avoid having to >> sign-extend by hand, but we can shift unsigned without losing anything. > > It gets us off the hook, but might introduce a 64-bit shift where > only a 32-bit shift was required.
Good point, but get_sleb128_step is only used from __libdw_get_sleb128, where the type is int64_t. This macro is not safe for outside use anyway, as it uses its parameters more than once. Hmm, should we maybe #undef it after __libdw_get_sleb128, so that it's clear that it's for local use only? Thanks, PM
