AnsiString(fp()) of a function-pointer PChar result mis-lowers — garbage length (SILENT)

• Type: bug (Track A — IsNodePChar / typecast lowering). SILENT (garbage length, heap over-read). Sibling of the now-fixed [[bug-pascal-ansistring-cast-of-cdecl-call-result]] (external direct-call variant).
• Status: done
• Found: 2026-07-17, sibling sweep after fixing the external-call variant.

Repro

type TPCharFn = function(n: PAnsiChar): PAnsiChar; cdecl;
function getenv(name: PAnsiChar): PAnsiChar; cdecl; external 'libc.so.6';
var fp: TPCharFn; s: AnsiString;
begin
  fp := @getenv;
  s := AnsiString(fp('PATH'));   { garbage length; direct getenv('PATH') is now correct }
end.

fwd(...) (forward-declared) and obj.Method(...) results cast correctly — only the indirect (function-pointer) call fails.

Root

The call is an AN_CALL_IND node (call through a proc-typed value), not AN_CALL. IsNodePChar (ir.inc:1494) enumerates node SHAPES and its case 4 keys on ASTIVal[node] as a procIdx — an indirect call has none, so no case matches → IsNodePChar returns False → the cast reinterprets the raw pointer as a managed handle → bogus length. Yet another shape the enumerator doesn't cover.

Fix

• Narrow: AN_CALL_IND stores ASTIVal[node] = the signature's Procs[] index (cpi, see ir.inc:5845). So the fix is two parts: (1) add an AN_CALL_IND case to IsNodePChar that checks ProcRetPtrElemTk[ASTIVal[node]] (mirroring case 4); (2) ensure the Pascal proc-type signature registration sets ProcRetPtrElemTk the way cparser does for C fn-pointer sigs (cparser.inc:3315) — if it doesn't, that's the same dropped-field bug as the external-decl path, one layer over. Verify (2) first (it may already be set, in which case only (1) is needed).
• Systemic (preferred): [[refactor-centralize-managed-string-pchar-conversion]] — key on the node's resolved static type instead of enumerating shapes. This bug and the external-call bug are its two motivating instances; the refactor kills both plus every future shape (ternary, index, with-field…) at once.

Acceptance

• The repro reports the correct length; a test/test_*.pas regression covers the fnptr-call cast.
• Gate: make test + self-host byte-identical.

Log

• 2026-07-17 — resolved, commit 9118a760.