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CLLTK_TRACEPOINT_FMT(buffer, "loaded {} in {}ms", name, ms) accepts
C++20 std::format placeholders. Validation happens at compile time
through a never-executed call to a helper taking std::format_string,
whose consteval constructor checks the literal against the argument
types - stronger than the printf attribute. Argument encoding is
unchanged (the library types arguments independently of format syntax);
the new meta entry type 5 only marks the syntax for decoders.
The varargs serializer is refactored around a va_list core so fmt
tracepoints get an entry point without the printf format attribute
({} strings must not be checked as printf formats). A char* argument
is always recorded as a string - {} has no printf %p/%s ambiguity.
C and kernel: not available (no compile-time {} validation exists
there); the macro fails with a static assert.
Signed-off-by: Jo5ta <jo5ta@mail.de>
Meta entry type 5 renders through the decoders' native {} formatters:
python str.format, C++ std::vformat. Arguments decode with the
existing type-array machinery including foreign-endian swapping; the
printf/ffi path is never touched for fmt entries. Formatting errors
degrade to the raw format string instead of failing the decode.
The C++ implementation wraps each decoded value in a small type with a
custom std::formatter that forwards the format spec, avoiding the
combinatorial std::visit-into-vformat instantiation blowup a naive
variant approach causes.
Signed-off-by: Jo5ta <jo5ta@mail.de>
Meta type mapping unit tests cover types 3-5. The integration test
compiles, runs, and decodes fmt tracepoints including format specs
({:x}, {:.2f}). Golden 1.6.0 fmt fixtures for aarch64 little endian
and s390x big endian validate both decoders against frozen files; the
generator gains a C++ writer that is skipped gracefully when
regenerating fixtures for versions without fmt support. The python
test harness target builds as C++20 (required by fmt tracepoints;
matches the examples). New example fmt_cpp shows usage including the
char*-as-string rule.
Signed-off-by: Jo5ta <jo5ta@mail.de>
README usage, file specification meta type 5, technical documentation of validation and rendering, AGENTS.md gotchas. New meta type is a file layout change: minor bump. Signed-off-by: Jo5ta <jo5ta@mail.de>
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Stack 6/7 — based on the export PR.
CLLTK_TRACEPOINT_FMT(buffer, "loaded {} in {}ms", name, ms)— std::format-style tracepoints for C++20, validated at compile time via a never-executedconstevalcheck againststd::format_string, so a malformed format or argument mismatch is a compile error. Runtime cost identical to printf tracepoints (same varargs core, refactored to a shared va_list path).__cpp_lib_format, kernel stub static-asserts with a clear message.str.format, C++ viastd::vformatwith a custom formatter wrapper over decoded arguments (avoids combinatorial visit instantiation).fmt_cpp, unit + integration tests, golden fixtures (LE and BE) with exact expected messages, docs.Version 1.6.0 (new meta entry type — layout addition).