Hint directives (deprecated / platform / experimental / …) on const/type/proc

• Type: feature (parser — FPC-compat dialect, Track A)
• Status: DONE 2026-07-04
• Owner: —
• Opened: 2026-07-04 (isolating the fgl "generics" wall — it was NOT generics; see [[fpc-lcl-compile-probe]])

Problem

FPC hint directives — deprecated ['msg'], platform, experimental, unimplemented, library — are accepted after a const value, a type declaration, and in a routine's modifier list. pxx rejects them:

const  MaxN = 1024 deprecated;                    { pascal26: unexpected token }
type   TOld = Integer deprecated;                 { unexpected token }
procedure P; deprecated; begin end;              { unexpected token }
procedure Q; deprecated 'use R instead'; begin end;

(var x: Integer deprecated; happens to already pass.) This is pervasive in real FPC RTL/FCL source — e.g. fgl.pp's MaxGListSize = MaxInt div 1024 deprecated; desyncs the parser and the error surfaces ~15 lines later as a misleading expected name, which read as a "generics" failure but is not.

Isolated repros

const K = 5 deprecated;          -> unexpected token
const K = 5 platform;            -> unexpected token
type  T = Integer deprecated;    -> unexpected token
procedure P; deprecated; ...     -> unexpected token

Fix (Track A, parser.inc)

Add a shared SkipHintDirectives that consumes a run of the hint words, where deprecated may be followed by an optional string message, then wire it at:

• Const section — ParseConstSection (~parser.inc:11100): after the const value, before the terminating ; (both typed and untyped const forms).
• Type section — ParseTypeSection (~parser.inc:11752): after the type, before the ;.
• Routine modifiers — the modifier lists that already handle inline/register/cdecl/… : the pre-scan skip loop (~parser.inc:13610) AND the real parse in ParseSubroutine (~parser.inc:13870+ modifier handling).

Semantics: parse-and-ignore is acceptable for v1 (no deprecation warning). A follow-up could emit warning: symbol 'X' is deprecated at use sites, but merely accepting the syntax is what unblocks compiling FPC source.

Acceptance

• The four isolated repros compile.
• fgl.pp no longer walls on the deprecated const (it advances to the next, separate gap — see [[feature-sizeof-const-intrinsic-in-const-eval]] and the uses types dependency).
• Self-host byte-identical; make test green; a regression .pas exercising a hint directive on const/type/proc.

Resolution (2026-07-04)

Added SkipHintDirectives (parser.inc, before ParseConstSection) — consumes a run of deprecated ['msg'] | platform | experimental | unimplemented | library (soft identifiers; deprecated takes an optional message string), parse-and- ignore. Wired at: const value end (ParseConstSection), type-alias end (ParseTypeSection), and both routine-modifier loops (the real ParseSubroutine modifier list + the pre-scan skip loop) where the hint words were folded into the existing inline/cdecl/… set. Verified across const/type/proc, deprecated 'msg', interleaving (inline; deprecated;), and that deprecated is still usable as an ordinary variable name (soft ident preserved). Self-host byte-identical; make test green; regression test/test_hint_sizeof.pas.