feat(cc): multi-declarator per-decl pointers + preprocessor stringify#494
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Extend parse_variable_declaration so additional declarators after the first may grow their own pointer depth on top of the shared base type (``const unsigned char *p = a, *q = b;``). The file-scope path already supported this shape; the local path now mirrors it by consuming optional ``*`` tokens between COMMA and IDENT, capped at parse_type's combined two-star limit. Unblocks ``user/libbboeos/string.c`` (memcmp opens with that exact declaration); parsing now advances past line 138.
Implement the C99 §6.10.3.2 stringify operator inside function-like macro replacement-lists. A ``#`` preceding a parameter name in the body now expands at the call site to a C string literal whose content is the unexpanded argument tokens joined with single spaces, with every ``"`` and ``\`` escaped. Two surface-area changes in cc/preprocessor.py: - ``_parse_function_define`` scans the body text for ``#<param>`` sequences before lexing; each becomes a ``STRINGIFY`` sentinel token, and a ``#`` not followed by a parameter raises CompileError at define time (rather than the previous ``unexpected character`` lexer error). - ``_expand_function_macro`` materialises ``STRINGIFY`` tokens into STRING literals via the new ``_stringify_argument`` helper, and fully macro-expands argument tokens before non-stringify substitution so the standard ``STR(x) STR2(x)`` / ``STR2(x) #x`` double-indirection trick exposes the expanded value. Unblocks ``user/libbboeos/signal.c`` (transitively pulls ``_SYSNUM_STR2(x) #x`` via ``<signal.h>``); parsing now advances past line 1.
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Summary
Two small cc.py features, each unblocking a Phase 6 libbboeos file.
parse_variable_declarationnow consumes optional*tokens between each,and IDENT (capped at parse_type's two-star combined limit), soconst unsigned char *p = a, *q = b;and similar shapes parse at function scope. The file-scope path already supported this; the local path now mirrors it. Unblocksuser/libbboeos/string.c(memcmp's exact declaration shape) — parsing now advances past line 138.#x). Function-like macro bodies may now contain#<parameter>;_parse_function_definelifts each match into aSTRINGIFYsentinel token (raising at define time when#does not precede a parameter), and_expand_function_macromaterialises those into STRING literals per C99 §6.10.3.2. Non-stringify parameter substitution now also fully macro-expands the argument tokens first, so the standardSTR(x) STR2(x)/STR2(x) #xdouble-indirection trick exposes the expanded value (e.g.SYSNUM_STR(SYS_RTC_ALARM)becomes"0x40"). Unblocksuser/libbboeos/signal.c— parsing now advances past line 1.Both probes still fail at later, expected, unrelated points (
*++pin string.c line 166;volatilein signal.c line 5).Test plan
python3 -m pytest tests/unit/ tests/test_ccobj.py tests/test_ccld.py tests/test_ccar.py -x -q— 567 passedpython3 tests/test_cc_local_structs.py— 9 / 9python3 tests/test_cc_bits.py— 112 / 112timeout 240 python3 tests/test_asm.py— 42 / 42 byte-equivalent./make_os.sh— clean build*++p)volatile)