C: anonymous struct global var with a NESTED anonymous enum member drops the declarator

• Type: bug (cparser global-var / struct-type parse). Track C.
• Found: 2026-07-08, surfaced by the new top-level stray-token error (bug-c-comment-terminator-greedy). c-testsuite 00120.

Symptom

struct { enum { X } x; } s;
int main(void){ return X; }

s (the variable declarator) is left unconsumed at top level → error: stray token at top level (not a declaration): 's'.

Isolation (2026-07-08)

• struct { int x; } s; — WORKS (plain anon-struct global var).
• enum { X }; at top level — WORKS.
• struct { enum { X } x; } s; — FAILS: the NESTED anonymous enum inside the anonymous struct body derails the type parse (global-var path parses the struct type but bails before the s declarator), so s; falls through to the top-level dispatch as stray tokens.

History

Before the top-level stray-token error existed, s and ; were silently skipped by ParseCProgram's else Next, and the nested enum X still resolved to 0 (the expected return), so 00120 PASSED BY ACCIDENT. The stray-token error (correctly, per gcc, for real garbage) now surfaces this as a hard failure — but 00120 is VALID C, so this is a genuine parse gap, not a stray-token false positive. Skipped in test/c-conformance/pxx.skip pending this fix.

Root cause (to confirm)

ParseCGlobalVarDecl (or the anon-struct type reader it calls) does not handle a nested anonymous enum { ... } inside an anonymous struct body — likely CStructBodyIsSimple / the field-type reader stops at the inner enum. Fix: parse a nested anon enum as a member type (register its enumerators in the enclosing scope, member type = int), then continue reading the struct body and the trailing declarator normally.

Gate

Drop 00120.c from test/c-conformance/pxx.skip; runner green; make test + self-host byte-identical.

Log

• 2026-07-08 — resolved, commit 42477beb.