+PP/30 Another attempt to deal with PCRE_PRERELEASE, this one less buggy.
+
+PP/31 %D in printf continues to cause issues (-Wformat=security), so for
+ now guard some of the printf checks behind WANT_DEEPER_PRINTF_CHECKS.
+ As part of this, removing so much warning spew let me fix some minor
+ real issues in debug logging.
+
+PP/32 GnuTLS was always using default tls_require_ciphers, due to a missing
+ assignment on my part. Fixed.
+
+PP/33 Added tls_dh_max_bits option, defaulting to current hard-coded limit
+ of NSS, for GnuTLS/NSS interop. Problem root cause diagnosis by
+ Janne Snabb (who went above and beyond: thank you).
+
+PP/34 Validate tls_require_ciphers on startup, since debugging an invalid
+ string otherwise requires a connection and a bunch more work and it's
+ relatively easy to get wrong. Should also expose TLS library linkage
+ problems.
+
+PP/35 Pull in <features.h> on Linux, for some portability edge-cases of
+ 64-bit ${eval} (JH/03).
+