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!

[konomikitten]

For me this was just my system running out of memory and the build process being killed by OOM:

Aug 29 19:20:49 debian earlyoom[719]: mem avail:   228 of  2399 MiB ( 9.54%), swap free:    0 of 7676 MiB ( 0.00%)
Aug 29 19:20:49 debian earlyoom[719]: low memory! at or below SIGTERM limits: mem 10.00%, swap 10.00%
Aug 29 19:20:49 debian earlyoom[719]: sending SIGTERM to process 55282 uid 1000 "cc1": oom_score 964, VmRSS 1585 MiB, cmdline "/usr/libexec/gcc/x86_64-linux-gnu/14/cc1 -quiet -I /home/debian/Git/helix-editor/helix/runtime/grammars/sources/gitcommit/src -imultiarch x86_64-linux-gnu /home/debian/Git/helix-editor/helix/runtime/grammars/sources/gitcommit/src/parser.c -quiet -dumpdir"
Aug 29 19:20:50 debian earlyoom[719]: kill_release: pid=55282: process_mrelease pidfd=4 success
Aug 29 19:20:50 debian earlyoom[719]: process 55282 exited after 0.100 seconds

I think that's why the stderr ouput isn't useful. Just wanted to add this in case anyone else came across the same problem. After closing some of my other programs there was enough memory to compile and the error went away.