Running the RNG is pointless if no seed is available because the key will be fixed. The computation just wastes time.
Previously, users could avoid this computation at least by asking for a context without signing capabilities. But since 3b0c218 we always build an ecmult_gen context, ignoring the context flags. Moreover, users could never avoid this pointless computation when asking for the creation of a signing context.
This fixes one item in #1065.
Running the RNG is pointless if no seed is available because the key
will be fixed. The computation just wastes time.
Previously, users could avoid this computation at least by asking for
a context without signing capabilities. But since 3b0c218 we always
build an ecmult_gen context, ignoring the context flags. Moreover,
users could never avoid this pointless computation when asking for
the creation of a signing context.
Whenever I read this code, I first think that rescaling ctx->initial is
a dead store because we overwrite it later with gb. But that's wrong.
The rescaling blinds the computation of gb and affects its result.
