Buildtid

Buildtid is a term used in some software tracing and crash reporting ecosystems to denote a composite identifier that ties a specific thread instance to the particular build of the running binary. It serves to uniquely identify the thread within a given executable image, enabling correlation of events across logs, profilers, and crash reports even when binaries are reloaded or rebuilt during a debugging session.

Generation and use: The exact representation of buildtid varies by platform and tool, but common implementations encode a build identifier (such as a build-id or a build timestamp) together with a thread identifier (tid) into a single value or a small pair. The loader or tracing runtime attaches the build identifier to the loaded image, and the operating system assigns the thread id. When events are recorded, the buildtid field allows precise mapping of those events to the specific binary version that produced them.

Relation to build-id: Buildtid is distinct from the ELF build-id embedded in an executable. The build-id identifies the binary image itself, while buildtid ties that image to a live thread instance. Combined with process and thread identifiers, buildtid helps reconstruct the exact execution state for debugging, profiling, and post-mortem analysis.

Limitations and scope: Buildtid is not a universal standard; it appears only in certain kernels, tracing frameworks, or crash-reporting tools. Representations, availability, and semantics can differ, and some environments may not expose a buildtid at all.

See also: build-id, thread ID (tid), process ID (pid), tracing, crash reporting. Example: a log line might show buildtid=0x7f2a1c4d, pid=1234, tid=5678 to correlate events with the corresponding binary build.