https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88662
Vincent Lefèvre <vincent-gcc at vinc17 dot net> changed:
What |Removed |Added
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CC| |vincent-gcc at vinc17 dot net
--- Comment #14 from Vincent Lefèvre <vincent-gcc at vinc17 dot net> ---
IMHO, this is implementation-defined, thus needs to be documented. 6.2.6.1p2
says
"Except for bit-fields, objects are composed of contiguous sequences of one or
more bytes, the number, order, and encoding of which are either explicitly
specified or implementation-defined."
And the combination of valid padding bits is part of the encoding.
If you fear that there may be any issue with a future change of GCC, you could
still say that this may change in the future.