Full name of submitter (unless configured in github; will be published with the issue): Jim X

The original issue is cplusplus/draft#5460.

[expr.prim.req.nested] says

The constraint-expression shall be satisfied ([temp.constr.decl]) by the substituted template arguments, if any.

We only define the concept "satisfied" for constraint, and there are only three kinds of constraints: conjunctions, disjunctions, and atomic constraints.

In [expr.prim.req.nested], constraint-expression is an expression but not a constraint, that is, before determining whether nested-requirement "satisfy", we should first normalize its constraint-expression to form the constraints.

Suggested Resolution

Make [temp.constr.normal] apply to the constraint-expression of nested-requirement to check whether the resulted constraint is satisfied.