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insv vs one-bit fields
- From: DJ Delorie <dj at redhat dot com>
- To: gcc at gcc dot gnu dot org
- Date: Fri, 2 Sep 2005 21:40:20 -0400
- Subject: insv vs one-bit fields
Why are one-bit bitfields not allowed? I'm trying to support a
BSET/BCLR pair that *only* support single bit fields, for I/O ports,
which are always volatile (and thus you have to use insv, as gcc won't
do a "or #1,port5" if port5 is volatile).
if (HAVE_insv
&& GET_MODE (value) != BLKmode
&& !(bitsize == 1 && GET_CODE (value) == CONST_INT)
So... why is it illegal to put a constant into a single bit field?