OpenMP support

ROUP models standardized OpenMP syntax from 1.0 through 6.0 for C, C++, and Fortran. These chapters describe the strict public behavior:

• Syntax catalogue and version policy
• Typed directive and clause components
• Validation boundaries

Version behavior

The default policy accepts the union of standardized historical syntax. An exact version rejects syntax introduced later while continuing to accept all older standardized syntax, including syntax deprecated or removed by the selected later specification.

Standard aliases are accepted and canonicalized into one semantic AST shape. Their introduction provenance participates in availability checks, and their checked source spans retain the exact physical location.

Strict typed behavior

A successful parse contains typed directive parameters, clause payloads, selectors, locators, allocator and induction records, and host expressions. Unknown syntax, malformed payloads, nonstandard extensions, invalid directive-clause combinations, duplicates, unavailable features, and trailing input are hard errors.

Optional semantic arguments added in OpenMP 6.0 are named Option<Expression> fields in their typed payloads. Historical bare forms remain accepted; empty parentheses never stand in for an omitted argument. Atomic compound spellings canonicalize to an atomic directive plus typed operation and memory-order clauses.

parse applies context-independent rules. parse_with_facts applies rules whose facts must come from an embedding compiler, and ContextValidator checks stateful region pairing across a sequence.

Regression coverage uses the configured public API in the feature-availability, context-validation, host-profile, source-span, directive-parameter, strict-payload, and strict-error test suites.