From b4fc9fed0c2d10cd8c1b3b99246b39c262ac5ade Mon Sep 17 00:00:00 2001 From: Gabriel Schneider Date: Thu, 24 Sep 2026 13:04:20 -0300 Subject: Allocate tree-sitter's external scanners from the same Zig allocator as its runtime syntax.zig points the tree-sitter runtime at a Zig allocator, but the grammars' external scanners did not follow it. A grammar's tree_sitter/alloc.h maps ts_malloc to the runtime's current allocator only when TREE_SITTER_REUSE_ALLOCATOR is defined, and plain malloc otherwise, so every scanner's state and its arrays came from libc. Five scanners (bash, markdown, markdown_inline, python, typst) also call malloc, calloc, realloc and free by name. build.zig now compiles every grammar with TREE_SITTER_REUSE_ALLOCATOR and forces in src/tree_sitter_heap.h, which includes stdlib.h and then defines the four names as calls through ts_current_malloc and friends. A header forced in from the build rather than a patch to the grammars keeps zig-pkg pristine. No grammar archive refers to libc's allocator any more; only the runtime does, for its defaults. A scanner frees only what it allocated itself, and the syntax tests that create and destroy a parser for every grammar under a leak-checking allocator pass. Co-Authored-By: Claude Opus 5.5 (1M context) --- src/syntax.zig | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'src/syntax.zig') diff --git a/src/syntax.zig b/src/syntax.zig index 5c8b9c0f..9c1a4f4b 100644 --- a/src/syntax.zig +++ b/src/syntax.zig @@ -140,8 +140,9 @@ fn initSpecs() [specCount()]Spec { var specs = initSpecs(); -/// What the tree-sitter runtime allocates from: `start`'s allocator, through -/// the shared C heap. +/// What tree-sitter allocates from, the runtime and every grammar's external +/// scanner (build.zig compiles them to use the runtime's allocator): +/// `start`'s allocator, through the shared C heap. var syntax_allocator: std.mem.Allocator = undefined; const syntax_heap = c_heap.Heap(&syntax_allocator); var syntax_started = false; -- cgit v1.3