On 1/5/24 15:01, Patrick Palka wrote:
Bootstrapped and regtested on x86_64-pc-linux-gnu, does this
look OK for trunk?
-- >8 --
Here during default template argument substitution we wrongly consider
the (substituted) default arguments v and vt<int> as value-dependent[1]
which ultimately leads to deduction failure for the calls.
The bogus value_dependent_expression_p result aside, I noticed
type_unification_real during default targ substitution keeps track of
whether all previous targs are known and non-dependent, as is the case
for these calls. And in such cases it should be safe to avoid checking
dependence of the substituted default targ and just assume it's not.
This patch implements this optimization, which lets us accept both
testcases by sidestepping the value_dependent_expression_p issue
altogether.
Hmm, maybe instead of substituting and asking if it's dependent, we
should specifically look for undeduced parameters.
Jason
