Do not enable lazy locking by default, because:
- It's fragile (applications can subvert detection of multi-threaded
mode).
- Thread caching amortizes locking overhead in the default
configuration.
Convert configuration-related cpp conditional logic to use static
constant variables, e.g.:
#ifdef JEMALLOC_DEBUG
[...]
#endif
becomes:
if (config_debug) {
[...]
}
The advantage is clearer, more concise code. The main disadvantage is
that data structures no longer have conditionally defined fields, so
they pay the cost of all fields regardless of whether they are used. In
practice, this is only a minor concern; config_stats will go away in an
upcoming change, and config_prof is the only other major feature that
depends on more than a few special-purpose fields.
Refactor the SO and REV such that they are set via autoconf variables,
@so@ and @rev@. These variables are both needed by the jemalloc.sh
script, so this unifies their definitions.
