Grammar build failure (cc1 takes 17 minutes)

[eminence]

I'm having troubles getting one specific grammar to build, and I need help debugging this problem

I'm using the latest 25.07 release:

achin@bbx in helix (5cda70e) is 📦 v25.7.0 🦀
❯ git log --oneline -1
5cda70e8 (HEAD, tag: 25.07, origin/master, origin/HEAD) Add changelog notes for 25.07 (#13939)

I'm building from source:

achin@bbx in helix (5cda70e) is 📦 v25.7.0 🦀
❯ cargo install --path helix-term --locked
  Installing helix-term v25.7.0 (/nas/achin/devel/helix/helix-term)
    Updating crates.io index
    Finished `release` profile [optimized] target(s) in 1.18s
   Replacing /home/achin/.cargo/bin/hx
    Replaced package `helix-term v25.7.0 (/nas/achin/devel/helix/helix-term)` with `helix-term v25.7.0 (/nas/achin/devel/helix/helix-term)` (executable `hx`)

achin@bbx in helix (5cda70e) is 📦 v25.7.0 🦀 took 4s
❯ hx --version
helix 25.07 (5cda70e8)

achin@bbx in helix (5cda70e) is 📦 v25.7.0 🦀
❯ echo $HELIX_RUNTIME
/nas/achin/devel/helix/runtime

Next I try to fetch and build the grammars:

achin@bbx in helix (5cda70e) is 📦 v25.7.0 🦀
❯ hx --grammar fetch
Fetching 245 grammars
245 up to date git grammars

achin@bbx in helix (5cda70e) is 📦 v25.7.0 🦀
❯ hx --grammar build
Building 245 grammars

At this point, things seem to hang.
Looking at a process listing, I see this command running, using 100% of 1 cpu core:

/usr/lib/gcc/x86_64-linux-gnu/12/cc1 -quiet -I /home/achin/.config/helix/runtime/grammars/sources/gitcommit/src -imultiarch x86_64-linux-gnu /home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/parser.c -quiet -dumpdir /home/achin/.config/helix/runtime/grammars/gitcommit.so- -dumpbase parser.c -dumpbase-ext .c -m64 -mtune=generic -march=x86-64 -O3 -Wall -Wextra -std=c11 -std=c11 -ffunction-sections -fdata-sections -fPIC -fno-exceptions -fasynchronous-unwind-tables -o /tmp/ccvcbCOU.s

Which is a subprocess of c++ (x86_64-linux-gnu-g++-12) which itself is a subprocess of hx

Memory usage for this cc1 process keeps increasing slowly (a few megabytes per second), but it definitely seems stuck. If I manually kill the cc1 process, I get this output from the grammar build process:

achin@bbx in helix (5cda70e) is 📦 v25.7.0 🦀
❯ hx --grammar build
Building 245 grammars
244 grammars already built
Failure 1/1: gitcommit Parser compilation failed.
Stdout:
Stderr: /home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c: In function 'tree_sitter_gitcommit_external_scanner_destroy':
/home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c:8:59: warning: unused parameter 'p' [-Wunused-parameter]
    8 | void tree_sitter_gitcommit_external_scanner_destroy(void *p) {}
      |                                                     ~~~~~~^
/home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c: In function 'tree_sitter_gitcommit_external_scanner_reset':
/home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c:10:57: warning: unused parameter 'p' [-Wunused-parameter]
   10 | void tree_sitter_gitcommit_external_scanner_reset(void *p) {}
      |                                                   ~~~~~~^
/home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c: In function 'tree_sitter_gitcommit_external_scanner_serialize':
/home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c:12:65: warning: unused parameter 'p' [-Wunused-parameter]
   12 | unsigned tree_sitter_gitcommit_external_scanner_serialize(void *p,
      |                                                           ~~~~~~^
/home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c:13:65: warning: unused parameter 'buffer' [-Wunused-parameter]
   13 |                                                           char *buffer) {
      |                                                           ~~~~~~^~~~~~
/home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c: In function 'tree_sitter_gitcommit_external_scanner_deserialize':
/home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c:17:63: warning: unused parameter 'p' [-Wunused-parameter]
   17 | void tree_sitter_gitcommit_external_scanner_deserialize(void *p, const char *b,
      |                                                         ~~~~~~^
/home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c:17:78: warning: unused parameter 'b' [-Wunused-parameter]
   17 | void tree_sitter_gitcommit_external_scanner_deserialize(void *p, const char *b,
      |                                                                  ~~~~~~~~~~~~^
/home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c:18:66: warning: unused parameter 'n' [-Wunused-parameter]
   18 |                                                         unsigned n) {}
      |                                                         ~~~~~~~~~^
/home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c: In function 'tree_sitter_gitcommit_external_scanner_scan':
/home/achin/.config/helix/runtime/grammars/sources/gitcommit/src/scanner.c:20:56: warning: unused parameter 'payload' [-Wunused-parameter]
   20 | bool tree_sitter_gitcommit_external_scanner_scan(void *payload, TSLexer *lexer,
      |                                                  ~~~~~~^~~~~~~
c++: fatal error: Terminated signal terminated program cc1
compilation terminated.

Error: 1 grammars failed to build

But this doesn't really tell me much.

This problem is 100% reproducible, and it always/only happens with the "gitcommit" grammar.

Any ideas how to debug this further?

[eminence]

Update: this grammar does actually build successfully, but it takes 17+ minutes

achin@bbx in helix (5cda70e) is 📦 v25.7.0 🦀
❯ hx --grammar build
Building 245 grammars
244 grammars already built
1 grammars built now
        ["gitcommit"]

achin@bbx in helix (5cda70e) is 📦 v25.7.0 🦀 took 17m14s

[lmas]

Thanks I've had the exact same issue. Good to know it did work eventually!