feat(cc): volatile keyword + prefix ++/-- on pointer deref#495
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Unblocks user/libbboeos/signal.c (and any other libbboeos file that
includes <signal.h>): the standard typedef `volatile int sig_atomic_t;`
was failing with `expected type, got IDENT ('volatile')`. cc.py has no
memory-model semantics, so `volatile` simply joins `const` / `signed`
in the leading no-op qualifier loop in parse_type.
Also adds `volatile` to KEYWORDS and TYPE_TOKENS so it lexes as its own
token kind and starts a declaration.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
Replaces the parser rejection of *++p / *--p (and *++p = expr; / *--p = expr;) with proper codegen. Semantics: prefix bumps the pointer by sizeof(*p) bytes first, then derefs through the updated pointer — what standard C requires for the `*++p = *src++;` copy / catenate idiom used in libbboeos/string.c. Lowering: the existing DerefIncrement / DerefIncrementAssign nodes now carry `is_postfix=False` for the prefix shapes. The x86 emitter calls `_emit_pointer_bump` *before* the load/store (and clears the accumulator before the prefix-read reload) so the rest of the codegen path is shared with the postfix forms. Unblocks user/libbboeos/string.c (failed at line ~166 on `*++p = *src++;` inside strncat-style routines). Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
cc.py's NUMBER regex matched only bare digits, so any C source that spelled an integer literal with a width / signedness suffix (``-1L``, ``0xFFFFFFFFu``, ``1ULL``) failed to tokenize — the suffix letter lexed as a separate IDENT and the parser then choked. The fix extends the NUMBER pattern to consume an optional trailing ``u`` / ``l`` combination (any case) and strips it in the lexer so the token text stays a plain integer string that ``int(...)`` can parse. cc.py has no real long / unsigned distinction at the literal level; the suffix just needs to lex. Unblocks user/libbboeos/stdio.c (failed at line 451 on ``pos == (off_t)-1 ? -1L : (long)pos``). Also documents the remaining dirent.c gap (line 315: ``sizeof *directory`` — ``sizeof`` of a unary-expression operand without parens, requires real sizeof-expression parsing). Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
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Summary
Three small cc.py feature additions that each unblock a Phase 6 libbboeos source file.
Commit 1 —
volatileno-op qualifier (cc/tokens.py,cc/parser.py:2120)Adds
volatileto KEYWORDS / TYPE_TOKENS and extends the leading qualifier loop inparse_typesoconst/signed/volatileall drop without semantics. Unblocksuser/libbboeos/signal.c(failed at line 5 ontypedef volatile int sig_atomic_t;).Commit 2 — prefix
*++p/*--p(cc/parser.py:1379,cc/parser.py:1587,cc/codegen/x86/emission.py:1808,cc/codegen/x86/emission.py:2978)Replaces the two parser rejection sites with real codegen. Lowering reuses
DerefIncrement/DerefIncrementAssignwithis_postfix=False; the x86 emitter calls_emit_pointer_bumpbefore the load / store (and clears the accumulator before the prefix-read reload). Read forms (*++p,*--p), write form (*++p = expr;), andchar */int *widths are all covered. Unblocksuser/libbboeos/string.c(failed around line 166 on*++p = *src++;inside strncat-style routines).Commit 3 — integer-literal suffix
L/U/LL/UL/ULL(cc/tokens.py:91,cc/lexer.py)NUMBER regex now consumes an optional trailing
u/lcombination (any case); the lexer strips the suffix so the token text stays a plain integer string. cc.py has no real long / unsigned distinction at the literal level — the suffix just needs to lex. Unblocksuser/libbboeos/stdio.c(failed at line 451 onpos == (off_t)-1 ? -1L : (long)pos).Investigation findings (not fixed in this PR)
user/libbboeos/dirent.c:315—DIR *directory = malloc(sizeof *directory);. cc.py only supportssizeof(type)/sizeof(var); the standardsizeofof a unary-expression operand without parens is a substantive parser feature (realsizeof <unary-expression>parsing with size-inference from the expression's type). Deferred.user/libbboeos/stdio.c— past line 451 fails at line 621 on adoubleliteral in a default-argument-like construct (expected expression, got DOUBLE). cc.py has no floating-point support; this is a separate, much larger gap.Test plan
python3 -m pytest tests/unit/ tests/test_ccobj.py tests/test_ccld.py tests/test_ccar.py -x -q— 572 passedpython3 tests/test_cc_local_structs.py— 9 / 9 passpython3 tests/test_cc_bits.py— 112 / 112 passpython3 tests/test_asm.py— 42 / 42 pass./make_os.sh— clean buildThree new unit tests cover
volatileparsing across typedef / global / parameter / local; four new unit tests cover prefix*++p/*--p(read char, read int, write char, decrement read) with assertions pinning the bump-before-load/store ordering; one new test covers integer-literal suffix lexing acrossL/u/UL/LL/uLL.Do not merge — leaving the PR open for review.
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