The conditional-compilation section promised zero overhead when telemetry is
not wanted. The span disappears, but the arguments passed to it do not: the
compiled-out guards are ordinary inline functions, so a to_string() or a hash
in an argument list still runs and its result is then discarded.
State that, show the guard that does remove the work, and name the opposite
case -- the metric macros, which discard their arguments and need no guard.
With telemetry compiled out, <string_view> in Telemetry.h and <memory> in
SpanGuard.h are named only by declarations that are themselves guarded, so
clang-tidy's include-cleaner reports them unused and warnings-as-errors fails
the build. NullTelemetry.cpp has the mirror problem: it names beast::Journal
only in the compiled-out makeTelemetry(), reaching the type transitively.
Guard each include to match the configuration that uses it, and correct three
comments that overstated what the empty destructors cost.
The compiled-out ScopedActivation, SpanGuard and ScopedSpanGuard each used a
defaulted destructor. A defaulted destructor on an empty class is trivial, so
compilers report any guard held only for its scope as an unused variable. With
telemetry compiled out that produced seven -Wunused-variable errors under
-Werror, across the ledger acquire, consensus, ledger master and overlay paths.
Write the three destructors by hand so destruction is not trivial, matching the
telemetry-enabled types, and assert that property so it cannot quietly regress
to `= default`. The bodies are empty, so no code is generated either way.
Also move <memory> inside the telemetry guard: only the telemetry-enabled types
hold a unique_ptr, so the include is unused when telemetry is compiled out.
The block was added on the StatsD branch, but telemetry sources start here.
Codecov config only flows child-ward, so every branch between this one and
that one kept reporting telemetry files as uncovered patch lines.
Also corrects the rationale. The old comment said telemetry is "not enabled
in coverage builds"; it is enabled — conanfile.py and CMakeLists.txt both
default it ON, and the coverage matrix leg does not turn it off. The reason
these files record no coverage is that the unit-test suite never starts an
exporter.
Adds *SpanLabels.h alongside *SpanNames.h: same compile-time-constant
category, and the existing glob did not match it.
This narrows the patch gap but does not close it — instrumentation added to
consensus and overlay files is still counted, so codecov/patch stays red on
the early phases.
The configuration reference typed the five trace_* switches as bool with
default true. An xrpld config section carries integers, and these keys are
read with an integer cast, so a literal "true" fails to convert rather
than enabling the switch.
Type them as 0 or 1 with default 1, matching the other integer-valued
keys in the same table.
