[sv-bc] static variable initializers

In section 11.6, there is text that says that variables declared in
a fork..join/join_any/join_none block shall be initialized whenever
execution enters their scope.

This text used to say "Automatic variables" in an earlier draft, but
this changed to just "Variables" in the standard.  This seems to imply
that static variables declared there would also be initialized at that
time.  It is bad enough that the text just says variables, but the
actual dropping of "automatic" from the older draft really seems to 
imply a change.  I assume that this was a mistake, and that the word
"automatic" should be added back.  Section 6.4 still says that statics
should be initialized at the start of simulation.  

The paragraph also says that reference arguments can be used in the
initialization values of variables in such blocks.  This only makes
sense for initializers executed on entry.  If static variables are
initialized at the start of simulation, it would make no sense for the
initializer to refer to a reference argument at that point.  So that
should specify automatic variables also.

I would also like to raise with the SV-EC another issue with static
variable initializers.  There used to be a requirement inserted by the
SV-BC that a static variable with an initializer had to be declared with
an explicit "static" keyword.  This requirement was deliberate, to help
avoid users becoming confused and thinking that the initializer would be
executed every time the block was entered.  This confusion could easily
happen, given that identical syntax could be either a static or automatic
variable declaration, depending on context.  Apparently this requirement
was removed by the SV-EC, without the SV-BC being aware of it.  We need
to understand why this was done.

Steven Sharp
sharp@cadence.com