C: zlib.h gzgetc function-like macro call fails to parse

• Type: bug (cfront — cpreproc/cparser, function-like macro). Track C.
• Found: 2026-07-06, zlib bring-up (2nd blocker after [[bug-c-typedef-name-as-uninitialized-local]], now fixed).
• Blocks: [[feature-c-corpus-zlib]].

Symptom

crtl + zlib.h + example.c fails to parse: Expected: ), but got: (Kind: 74, Line: N) near: gzgetc >>> file (the Kind: 74 is just the error-reporter's token number, not meaningful.)

example.c calls gzgetc(file). zlib.h defines gzgetc as a function-like macro that inlines the fast path and falls back to a parenthesized function-name call:

#define gzgetc(g) \
    ((g)->x.have ? (--(g)->x.have, (g)->x.pos++, *((g)->x.next)++) : (gzgetc)(g))

Two candidate triggers to isolate (reduce to a minimal repro first):

1. a function-like macro whose body is a parenthesized comma-expression;
2. the (gzgetc)(g) parenthesized-function-name call in the fallback arm (calling through (name) where name is also the macro under expansion).

Next

Reduce to a minimal repro vs gcc, decide preproc-vs-parser, fix, add a regression test. Then zlib's runner should get past example.c parsing.

Gate

crtl + zlib.h + example.c parses; make test-zlib advances.

RESOLVED 2026-07-07 (Track A+C, sole-A)

Isolated: NOT the comma-expression macro body (that always worked). The parse failure Expected ), but got ( was the (gzgetc)(g) parenthesized-function- name call. A bare function name in parens decays to AN_PROCADDR (its address); CNodeProcSig had no AN_PROCADDR case, so the trailing (args) was never applied as a call and the postfix layer choked. Fix (cparser.inc CNodeProcSig): an AN_PROCADDR callee's own proc index IS its call signature → (name)(args) lowers to an indirect call through the address. Self-referential blue-paint already handled (macro name not re-expanded inside its own body).

Result: zlib's example.c now PARSES, COMPILES and LINKS the runner (was parse-blocked). test-zlib advanced from parse-fail to a link-stage undefined symbol: gz_error — a separate zlib-internal-symbol issue, filed under [[feature-c-corpus-zlib]], NOT this macro bug. Regression b171 (parenthesized name call + self-ref macro fallback). make test self-host byte-identical; c-conformance 195/0.