[danusha2345]

Stacked on #1733 (its commit comes first; rebases to one commit once that lands). Together they close the C extraction extent problem behind #1729: after #1733 a 2,109-file betaflight tree still had 265 C functions the graph filed inside another function; after this, 5.

What the 265 were

Not one cause, and mostly not real functions. 192 of them are literally named if, the rest (NVIC_PRIO_TIMER), (reg), ATMEL_DEVICE_MATCH — phantoms. Verified shape by shape with the shipped tree-sitter-c.wasm:

1. A #if branch that begins with else. tree-sitter-c parses each preprocessor branch as a run of block items, and else cannot start one, so the if (cond) { … } that follows is read as a K&R implicit-int function definition named if, nested in the enclosing function:

   void f(int id) {
       if (id == 1) { a(id); }
   #ifdef USE_V
       else if (id == 2) { b(id); }
   #endif
       else { c(id); }
   }

   (current.c, stm32*_ll_usart.c, _ll_tim.c, _ll_gpio.c, flash_w25n.c, …)
2. A branch that ends with a bare if (…) / else if (…) header whose { body sits after #endif — the STM32H7 ll_utils.c latency tables, 24 phantoms in one file.
3. Branches that leave braces unbalanced (CMSIS arm_mat_*, smartport.c, bus_spi_ll.c): here the enclosing function vanished entirely and its locals leaked to file scope — arm_mat_mult_q15.c had zero function nodes.
4. All-caps block macros in statement position — ATOMIC_BLOCK(NVIC_PRIO_MAX) {, PG_FOREACH(reg) { — which blankCStatementMacroCalls matched in lowercase only.

The fix

blankCUnbalancedConditionalBranches: for a #if … #else/#elif … #endif group where any branch shows one of shapes 1–3, keep the first branch not written #if 0 verbatim and blank every other branch and the group's directive lines (continuations included) to spaces, newlines kept. Balanced groups are untouched; innermost groups first. It runs at the tail of preParseCSource, after restoreDirectiveLines, for the same reason blankCNamedVariadicDefineDots does — it edits directive lines deliberately. blankCStatementMacroCalls also accepts [A-Z_][A-Z0-9_]* now (PascalCase still excluded, for the C++-constructor reason in its comment). The C++ grammar parses both snippets cleanly, so the C++ path is left alone; the pre-parse precedes the kernel route point, so the kernel needs no change.

Measured

betaflight fork, 2,109 .c files, wasm arm:

	#1733	this
C functions nested inside another C function	265	5
C function nodes	39,993	39,772 (260 phantoms gone, ~39 real functions back)
fuzzy calls	154	37

Edge-set delta against the #1733 index, rows keyed with resolvedBy: 1,263 lost / 729 gained. Lost: 709 exact-match calls whose source was a phantom (if@…) or a file node holding leaked locals, 490 file-level contains for those locals (pInA, row, flag), 53 references, 11 function-refs. Gained: 671 exact-match calls from the recovered functions (USBD_LL_Init → HAL_PCD_Init, LL_TIM_DeInit → …, processSmartPortTelemetry → erpmToRpm) and 43 contains for them. Functions that now exist with their real extents: spiInternalInitStream/StartDMA/StopDMA (bus_spi_ll.c), processSmartPortTelemetry (522–903), esc4wayProcess (429–929), arm_mat_mult_q15. Ten lost and ten gained rows read against source: every lost row is a re-attribution from a phantom or a file node, not a real call gone.

The 5 that remain: four if SILABS_DEVICE_MATCH { / else if ATMEL_DEVICE_MATCH { in serial_4way.c (a paren-less macro as an if condition) and one STATIC_DMA_DATA_AUTO union { … } testBuffer; in flashfs.c — each its own narrow blank, not folded in here.

Tests

extraction.test.ts: a unit test of the blank (length and line count preserved, a continuation line blanked, the first branch kept, the second branch and the directives blanked, a balanced #ifdef untouched, #if 0 keeps the live branch, identity on a file without groups) and an end-to-end index where a function after a damaged group used to be a phantom (NVIC_PRIO_MAX) and now has its own extent and top-level name; the end-to-end test fails without the change. extraction.test.ts + resolution.test.ts: 815, tsc clean.

🤖 Generated with Claude Code

[danusha2345]

Rebased onto current main (2f1a99d): head 9ce9e30, one commit. The #1733 commit this was stacked on is dropped since #1755 landed the same blanking; the #if collapse applies cleanly on top of it. tsc clean; the C extraction tests pass.

[danusha2345]

Second commit, b0ed0d1, from running the branch on two more C trees.

jq lost main. src/main.c has #ifdef WIN32 int umain(…) { #else int main(…) { #endif — two function heads in one group. Keeping the first branch kept the WIN32 head, and main (289–730) was gone from the index. The survivor is now the default-build branch: a group that opens on a feature test (#ifdef X, #if defined(X), #if X) and has an #else keeps the #else branch; #ifndef / #if !… keep the first; #if 0 the live one. jq: main back, phantom if functions 1 → 0, fuzzy 23 → 0.

Two more damage shapes (betaflight, the 7 phantom ifs the first cut left): a branch that is a fragment of an expression — || (hopamp4 == NULL) inside an if (…) in the STM32 HAL, isEmpty(cmdline) || before the rest of a condition in cli.c — and a branch that opens with } else if (…) {, closing a block it did not open. Betaflight (2,109 C files, main at cd4e65b which has #1755): phantom if 203 → 0; edges −1,339 / +1,429 against main, the removals re-attributions off file-level nodes and the additions the members of enums that now parse (IRQn_Type). Fixtures for all three shapes are in the test; the first test's expectations flipped to the #else branch.

[danusha2345]

Merged current main (1f4379d, post-#1804) into this branch: head 1c261bc. One conflict, the tail of the C pre-parse pipeline: #1804 wraps it in the raw-string restore, this PR adds the #if-group collapse. Composed as restore ∘ collapse ∘ variadic-define ∘ directive-restore — the collapse is length-preserving, and it counts braces with raw-string bodies still masked, so a brace inside R"(...)" can't trip it. tsc clean; extraction, cpp-raw-string-delimiter-haserror and cpp-raw-string-preparse-1505 pass (697 tests).

[danusha2345]

Merged current main (7a23648) into this branch: head 8dff394. The only conflict was the CHANGELOG entry; no source conflict. tsc clean, the branch's tests pass.

[colbymchenry]

Thanks @danusha2345! Your pass landed in #2940 with you as the commit author, and it clears every phantom if function on betaflight, the ST HALs, redis and jq. We changed one thing in how a damaged group is opened: when each branch balances on its own, all branches now stay and only the directive lines go, because keeping one branch dropped real code, like betaflight's rescue-plan arms in failsafe.c and adc_stm32h7xx.c's adcTagMap. Groups that don't balance, and #if 0/#if 1, still keep one branch as you designed. We also fixed a few edge cases: braces inside multi-line comments (Lua's banners), a \ splice inside a comment, a directive right under a kept branch, and #if 1. The CHANGELOG line is reworded without numbers. It ships in the next release.