Autoconf's AC_CHECK_DECLS always defines HAVE_DECL_whatever
as 1 or 0, but some of the entries in msvc/Solution.pm show
such symbols as "undef" instead. Shouldn't we fix it as
per attached? This is probably only cosmetic at the moment,
but it could bite us someday if someone wrote a complex
conditional using one of these symbols.
These apparently-bogus values date to Peter's 8f4fb4c64,
which created that table; but AFAICS it was just faithfully
emulating the previous confused state of affairs.
regards, tom lane