Crate mbx_cache_cc 

Conservative parsing and action-key construction for C and C++ compiles.

Cargo build scripts using the cc crate compile C and C++ through a gcc-style driver. This adapter models the narrow shape those build scripts produce – one source, one object, -c – and rejects everything else. As in the rustc adapter, callers should treat CcBypassReason as a safe cache bypass: run the real compiler and publish nothing.

Two properties separate this adapter from a traditional compiler cache. Preprocessor inputs are discovered from a depfile the adapter injects itself, so the key names the headers the compilation actually read; and the directories those headers were searched from contribute a name manifest, so a header that newly shadows one of them changes the key even though every previously-read file is byte-identical.

Path mappings are shared with the rustc adapter so both agree on which host roots are checkout-specific.

Structs

CcAction

Canonical action descriptor and its content digest.

CcActionContext

External information needed to construct a canonical cc action.

CcActionInput

One file input paired with the digest used in the action key.

CcCompilerIdentity

Compiler properties that distinguish incompatible objects.

CcDepfile

A parsed GNU-style dependency list.

CcDiscoveredInputs

A complete, content-addressed compiler input manifest.

CcInputPrediction

Normalized input names from the last successful execution of one modeled compile.

CcInvocation

A parsed, admitted C or C++ compile.

Enums

CcBypassReason

Reason a C or C++ invocation cannot safely use the action cache.

CcCompilerFamily

Compiler family, which decides how the identity is assembled.

CcLanguage

Source language a driver invocation compiles.

Constants

ACTION_SCHEMA_VERSION

Schema version embedded in canonical cc action descriptors.

ADAPTER_VERSION

Version of the cc argument and input model used to construct keys.

BYPASS_ENVIRONMENT

Environment variables that force a bypass when set.

INCLUDE_MANIFEST_PREFIX

Marker distinguishing an include-directory name manifest from a file input.

KEYED_ENVIRONMENT

Environment variables whose values enter every cc action key.

MAX_INPUT_BYTES

Maximum total bytes digested for one action.

MAX_MANIFEST_ENTRIES

Maximum file names summarized across all include manifests.

MAX_PREDICTED_INPUTS

Maximum discovered inputs, including include-manifest entries.

SYSTEM_ROOTS

Absolute roots whose contents are keyed verbatim rather than through a placeholder.

Functions

environment_inputs

Read the modeled environment, rejecting variables that change the compile in a way the argv model cannot see.

environment_inputs_for

Read the modeled environment for a particular compiler family.

is_system_path

Whether a path lies beneath a root whose location is a machine property.

manifest_snapshot

Digest the includable names in each directory, reading no file contents.