Delayed init was introduced 2019-02-19 in ef5e30056 and was lazy init at
that time, matching the name.
This changed 2020-05-19 in 4eb78f5c8, when auto-init was added, making
delayed init not delayed anymore.
While the option is still needed to make manual lifetime work, and it has
to be enabled on apple, there's no reason anymore to expose it to users.
Extension point so private/unsupported platforms can plug in their own implementations of the kernel/libc primitives Tracy depends on, without patching the `#if`/`#elif` chains.
Projects supply a platform header via `-DTRACY_PLATFORM_HEADER="\"my_platform.h\""` at build time. Tracy includes it in any TU that needs the hooks. The header toggles per-category `TRACY_HAS_CUSTOM_*` macros and declares matching `tracy::Platform*` functions.
Available hooks:
- `TRACY_HAS_CUSTOM_THREAD_ID` → `PlatformGetThreadId`
- `TRACY_HAS_CUSTOM_USER_INFO` → `PlatformGetHostname`, `PlatformGetUserLogin`, `PlatformGetUserFullName`
- `TRACY_HAS_CUSTOM_SAFE_COPY` → `PlatformSafeMemcpy`
- `TRACY_HAS_CUSTOM_ALLOCATOR` → `PlatformMalloc`, `PlatformFree`, `PlatformRealloc`, `PlatformAllocatorInit`, `PlatformAllocatorThreadInit`, `PlatformAllocatorFinalize`, `PlatformAllocatorThreadFinalize`
Each hook is wired as the first arm of its respective `#if`/`#elif` chain, so existing supported platforms are unaffected.
Template files in `examples/CustomPlatform/` and a new subsection in `manual/tracy.tex` document the mechanism.
The documentation states that Tracy is disabled by default, but the
build system defaults were ON/true. Change CMake and Meson defaults to
OFF/false. Projects that need profiling enabled must now opt in
explicitly. Add explicit TRACY_ENABLE=ON / tracy_enable=true to CI
steps and the test project to preserve existing behavior.
